Answer:
y = -5
General Formulas and Concepts:
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightDistributive Property
Equality Properties
Multiplication Property of Equality Division Property of Equality Addition Property of Equality Subtraction Property of EqualityStep-by-step explanation:
Step 1: Define
Identify
-2(y - 4) = 18
Step 2: Solve for y
[Distributive Property] Distribute -2: -2y + 8 = 18[Subtraction Property of Equality] Subtract 8 on both sides: -2y = 10[Division Property of Equality] Divide -2 on both sides: y = -5An educator wants to determine whether early exposure to school will affect IQ. He enlists the aid of the parents of 12 pairs of preschool-age identical twins who agree to let their twins participate in this experiment. One member of each twin pair is enrolled in preschool for 2 years while the other member of each pair remains at home. At the end of the 2 years, the IQs of all the children are measured. The results follow.
IQ
Pair Twins at
preschool Twins at
home
1 109 116
2 122 119
3 110 106
4 119 115
5 114 118
6 112 103
7 128 125
8 114 116
9 108 107
10 117 123
11 117 116
12 106 104
Does early exposure to school affect IQ? Use α = 0.052 tail.
tobt =
There are several vehicles in a parking lot. Some of them are motorcycles
(with 2 wheels), and some are cars (with 4 wheels). There are 10 vehicles in
the lot, and there are 32 wheels. How many vehicles of each type are in the
lot?
Answer:
There are four motorcycles and six cars.
Step-by-step explanation:
Let m represent the number of motorcycles and c represent the number of cars.
Since there are ten vehicles in total, the sum of the number of motorcycles and the number of cars must total ten. Hence:
[tex]m+c=10[/tex]
And since each motorcycle has two wheels and each car has four wheels and there are 32 wheels in total:
[tex]2m+4c=32[/tex]
Solve the system of equations. First, we can divide the second equation by two:
[tex]m+2c=16[/tex]
From the first equation, we can subtract c from both sides:
[tex]m=10-c[/tex]
Substitute:
[tex](10-c)+2c=16[/tex]
Simplify:
[tex]10+c=16[/tex]
Therefore:
[tex]c=6[/tex]
There are six cars.
Using the modified equation:
[tex]m=10-c[/tex]
Solve for m:
[tex]m=10-(6)=4[/tex]
So, there are four motorcycles and six cars.
Evaluate u + xy, for u = 20, x = 5, and y = 7.
Answer:
55
Step-by-step explanation:
u + xy, for u = 20, x = 5, and y = 7
u + xy = 20 + 5 * 7 = 20 + 35 = 55
Step-by-step explanation:
hear is your please check attachment
Can anyone please help me with this ? Thanks 2.5m = 75
2.5m = 75
To find m divide both sides by 2.5:
M = 75/2.5
M = 30
Answer:
m = 30
Step-by-step explanation:
2.5 m = 75
To find m divide 75 by 25
m = 75 / 2.5
m = 30
Find the slope from the given equation. 9y = -3x + 5
Answer:
-3/9x
Step-by-step explanation:
You rearrange for 'y' so divide both sides by it's coefficient which is 9.
Answer:
The slope is -1/3
Plzzz someone help me , ur flippin amazing if u help me :)
Answer:
C ................................. I think
Is 12 rational? irrational? Whole? Integer?
Answer:
It is an Integer, but it can also be a rational number.
Step-by-step explanation:
My math teacher told meh
area of a trapezium.
Answer:
Step-by-step explanation:
A= (a + b) * h/2
Answer:
what they said
Step-by-step explanation:
yeah what they said
i will mark brainliest
which statement best describes the are of Triangle ABC shown below?
A: it is going to have the area of a square of side lengths 6 units.
B it is twice the area of a square of side lengths 6 units.
C is one half the area of a rectangle with sides 6 units * 2 units.
Dit is twice the area of a rectangle with sides 6 units comes with two units.
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Answer:
C is one half the area of a rectangle with sides 6 units * 2 units
Step-by-step explanation:
The area of any triangle is half the area of a rectangle of the same height and width. Here, the triangle has a width of 6 units and a height of 2 units. Its area is ...
one half the area of a rectangle with sides 6 units by 2 units
someone please help! (listing BRAINLIST and giving points) :)
thx thx thx thx thx thx thx sa points sabi mo give away eh
I hope this is help full to you
Kathleen hiked to the top of a mountain. She started the hike at 7:25 A.M. It took 3 hours and 45 minutes to get to the top of the mountain and 1 hour and 30 minutes to hike back down. What time was it when Kathleen finished the hike?
Answer: 11:45 am
Step-by-step explanation:
10:15
toget back down 10
;15
help urgent please
the graphs below have the same shape. what is the equation of the blue graph?
no links please
Answer:
D
Step-by-step explanation:
If you add or subtract three outside of the exponent (ex: x^2 + 3), then the parabola moves up and down.
If you add or subtract the number inside the exponent (ex: (x+3)^2), then the parabola moves side to side.
If you add three, the parabola moves left.
Thus, the answer is D.
Decrease
M720.00 by 25%
Answer:
540
Step-by-step explanation:
720 (100-25) to find the decimal to use (below 1.00 is decreasing)
720 (.75) = 540
please help i am actually so confused on this one
Answer:
C
Step-by-step explanation:
Using pythagoras theorem, you will find that AC= 12,
[tex]\sqrt{13^2-5^2}= 12[/tex]
Sin A = Opposite / Hypotenuse, in this case the opposite of A is CB which is 5ft, and then Hypotenuse of the right angled triangle is AB. which is 13ft.
So, Sin A = 5/13
Tan A= Opposite/ Adjacent,
Opposite is CB, which is 5ft, adjacent is AC, which is 12ft.
So, Tan A= 5/12
Cos A= Adjacent/Hypotenuse,
we know adjacent is 12ft and that hypotenuse is 13ft.
So Cos A= 12/13
However Sec A is the inverse of cos A.
So, Sec A= 13/12.
x=ky a. if x=15 when y=14.find the value of k.. b..Find x when y=70 c...find y when x=45
Step-by-step explanation:
Given that,
a. x = 15 and y = 14
The equation is :
x = ky
or
[tex]k=\dfrac{x}{y}[/tex]
Put all the values,
[tex]k=\dfrac{15}{14}\\\\k=1.07[/tex]
b. Now, put y = 70 and k = 1.07.
x = 1.07×70
x = 74.9
c.
Put x = 45 and k = 1.07.
[tex]y=\dfrac{x}{k}\\\\y=\dfrac{45}{1.07}\\\\y=42.05[/tex]
Hence, this is the required solution.
A pair of shoes that normally cost $24 is 25% off. what is the selling price of the jeans?
Answer:
The selling price of the shoe is $18
Step-by-step explanation:
Hey there!
According to the question, the normal cost price of pair of shoes is $24 (i.e $24 is MP= marked price).
Also, there is 25% off. (i.e discount)
Now,
SP (selling price) = MP - discount% of MP
or, SP = 24 - 25% of 24
or, SP= 24 - 6
Therefore, the SP of the shoes is $18.
Hope it helps!
$18
The answer is $18
(x^2+2x-1)+(2x^2 – 2x+1)
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Answer:
3x^2
Step-by-step explanation:
Add coefficients of like terms.
(x^2 +2x -1) +(2x^2 -2x +1)
= (1 +2)x^2 +(2 -2)x +(-1 +1)
= 3x^2 +0x +0
= 3x^2
Answer:
3x^2
Step-by-step explanation:
(x^2+2x−1)+(2x^2−2x+1)
Combine x^2 and 2x^2 to get 3x^2.
3x^2+2x−1−2x+1
Combine 2x and −2x to get 0.
3x ^2−1+1
Add −1 and 1 to get 0.
3x^2
What is the value of y?
Using the Pythagorean theorem,
[tex]6^{2}+y^{2}=(3+9)^{2}\\\\36+y^2=144\\\\y^2=108\\\\y=\boxed{6\sqrt{3}}[/tex]
A museum conducts a survey of its visitors in order to assess the popularity of a device which
is used to provide information on the museum exhibits. The device will be withdrawn if fewer
than 20% of all of the museum’s visitors make use of it. Of a random sample of 100 visitors,
15 chose to use the device.
i. Carry out an appropriate hypothesis test at the 5% significance level to
see if the device should be withdrawn and state your conclusions.
ii. Calculate the p-value of the test
Answer:
i:
The appropriate null hypothesis is [tex]H_0: p \geq 0.2[/tex]
The appropriate alternative hypothesis is [tex]H_1: p < 0.2[/tex]
The p-value of the test is 0.1057 > 0.05, which means that there is not sufficient evidence that fewer than 20% of the museum visitors make use of the device, and so, it should not be withdrawn.
ii:
The p-value of the test is 0.1057
Step-by-step explanation:
Question i:
The device will be withdrawn if fewer than 20% of all of the museum’s visitors make use of it.
At the null hypothesis, we test if the proportion is of at least 20%, that is:
[tex]H_0: p \geq 0.2[/tex]
At the alternative hypothesis, we test if the proportion is less than 20%, that is:
[tex]H_1: p < 0.2[/tex]
The test statistic is:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, [tex]\sigma[/tex] is the standard deviation and n is the size of the sample.
0.2 is tested at the null hypothesis:
This means that [tex]\mu = 0.2, \sigma = \sqrt{0.2*0.8} = \sqrt{0.16} = 0.4[/tex].
The device will be withdrawn if fewer than 20% of all of the museum’s visitors make use of it. Of a random sample of 100 visitors, 15 chose to use the device.
This means that [tex]n = 100, X = \frac{15}{100} = 0.15[/tex]
Test statistic:
[tex]z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}[/tex]
[tex]z = \frac{0.15 - 0.20}{\frac{0.4}{\sqrt{100}}}[/tex]
[tex]z = -1.25[/tex]
P-value of the test and decision:
The p-value of the test is the probability of finding a sample proportion below 0.15, which is the p-value of z = -1.25.
Looking at the z-table, z = -1.25 has a p-value of 0.1057.
The p-value of the test is 0.1057 > 0.05, which means that there is not sufficient evidence that fewer than 20% of the museum visitors make use of the device, and so, it should not be withdrawn.
Question ii:
The p-value of the test is 0.1057
9 sprinters have made it to the Olympic finals in the 100-meter race. In how many different ways can the
gold, silver, and bronze medals be awarded?
Answer:
in three different ways the first one gets a gold one the other 4 printers get silver n the last 4 printers get bronze.
the two solids below are similar and the ratio between the lengths of their edges is 4:7 what is the ratio of their surface areas? A 7:4 B 16:49 C 16:29 B 64:343
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Answer:
B. 16:49
Step-by-step explanation:
The area ratio is the square of the edge length ratio:
area ratio = (4:7)² = 4²:7² = 16:49
_____
It might help you to recall that area is the product of two linear dimensions if each is multiplied by 4/7, the resulting product will be multiplied by (4/7)².
A = LW
A' = (4/7L)(4/7W) = (4/7)²(LW) = (16/49)·A
help me out pleaseeee
Answer:
The correct option is (b).
Step-by-step explanation:
The solution of the given polynomial is :
[tex](-\dfrac{1}{3},4)[/tex]
x = 1/3 and y = -4
i.e.
Sum of roots = (1/3-4) = -11/3
Product of roots = (1/3)(-4) = -4/3
The quadratic equation is as follows :
[tex]x^2+(\text{sum of roots})x+\text{Product of roots}=0[/tex]
Put all the values,
[tex]x^2+\dfrac{-11}{3}x+\dfrac{-4}{3}=0\\\\3x^2-11x-4=0[/tex]
So, the correct option is (b).
please answer thank you
Answer:
37 / 16
Step-by-step explanation:
_____________________
Can someone help pleaseee
Answer:
Ŷ = 76.4064+5.4254X
0.786
Strong positive relationship
Score = 98
Step-by-step explanation:
Using technology, the linear model obtained by fitting the data is :
Ŷ = 76.4064+5.4254X
Where, slope = 5.4254
y = test score ; x = study time
The Correlation Coefficient obtained is 0.786 ; which depicts that there exist a strong positive relationship between the two variables.
Using the model; test score, if x = 4
Ŷ = 76.4064+5.4254(4)
Y = 98.108
Test score = 98
A person's Body Mass Index (BMI) is a measure of the amount of fat in their body. The relationship between antioxidant food consumption per day in cups and the BMI of an individual is modeled by the following line of best fit: [tex]y=-1.2x+26[/tex] . Interpret the slope and intercept of the trend line within the context of the data.
DIRTY ANSWERS REPORTED
NO LINKS ALLOWED!
Answer:
The slope of -1.2 means that for each cup of antioxidant a person consumes per day, it's BMI decreases by 1.2.
The intercept of 26 means that a person that does not consume any cup of antioxidant food a day should have an BMI around 26.
Step-by-step explanation:
Line of best fit:
[tex]y = -1.2x + 26[/tex]
Slope:
The slope is the number that multiplies x, that is, -1.2. The slope of -1.2 means that for each cup of antioxidant food a person consumes per day, it's BMI decreases by 1.2.
Intercept:
Value of y when x = 0, that is, 26. The intercept of 26 means that a person that does not consume any cup of antioxidant food a day should have an BMI around 26.
Answer:
the slope is -1.2 and the intercept is 26.
Step-by-step explanation:
our line's equation is y= -1.2x + 26
In the equation y = mx + b, m is the slope and b is the y-intercept. So in this equation, look for where the numbers are placed and that it what you get.
The distance that students drive to school is best modeled with a skewed right distribution that has a mean of 10 miles and a standard deviation of 2 miles. Suppose a sample of 100 students has been taken and the sample mean distance for the sample is calculated. Describe the shape of the sampling distribution of the sample mean
Answer:
The answer is "Approximately normal".
Step-by-step explanation:
sample size[tex]n=100[/tex]
Sample size [tex]n \geq 30[/tex]
It is because [tex]C \perp T[/tex] the sampling distribution of the sample means is approximately normal.
Which is a stretch of an exponential decay function?
f(x)=4/5(5/4)x
f(x)=4/5(4/5)x
f(x)=5/4(4/5)x
f(x)=5/4(5/4)x
If you apply the changes below to the reciprocal parent function, F(x) =
what is the equation of the new function?
• Horizontally stretch by multiplying by 1/6
• Translate 5 units right.
Answer:
The answer is "Option B".
Step-by-step explanation:
Please find the complete question in the attached file.
The Horizontal stretch [tex]=(\frac{1}{6 \ x})\\\\[/tex]
Translation by 5 units right[tex]=( \frac{1}{6\ x})-5[/tex]
Answer:
its A i used his answer and got it wrong
round 5763 to the nearest hundred
Answer:
[tex]5800[/tex]
Step-by-step explanation:
Hope it is helpful...
Answer:
5800
Step-by-step explanation:
5763
7 is in the hundreds place
We look at the tens place to determine how to round
If the tens place is 5 or above we round up, if it is 4 or less- leave it alone
Since 6 is 5 or above, we round the 7 up
5763 rounds to 5800
A comet travels at an average speed of 233,000 km/h.
It takes 7 days for the comet to reach Earth.
Find the distance, in km, the comet travelled.
Answer:
39,144,000 km
Step-by-step explanation:
Hi there!
Distance traveled = time * speed
Given speed: 233000 km/h
Given time: 7 days
It's important to note that our speed is given in per hours and out time is given in days. So in order to find how far the comet has traveled we must convert days to hours.
There are 24 hours in 1 day.
So to convert days to hours simply multiply amount of days by 24
24 * 7 = 168
So the comet has traveled for 168 hours
Now we can find distance traveled
Once again distance traveled = time * speed
Given speed is 233000 km/h
Given time is 168 hours
Distance = 168 * 233000 = 39,144,000
So the comet has traveled for a total distance of 39,144,000 km