Answer:
- (b - 9)(b + 8)
Step-by-step explanation:
72 + b - b² ← factor out - 1 from each term and rearrange into standard form
= - (b² - b - 72) ← factor the quadratic
Consider the factors of the constant term (- 72) which sum to give the coefficient of the b- term (- 1)
The factors are - 9 and + 8
Use these factors to split the b- term
b² - 9b + 8b - 72 ( factor the first/second and third/fourth terms )
b(b - 9) + 8(b - 9) ← factor out (b - 9) from each term
(b - 9)(b + 8)
Then
72 + b - b² = - (b - 9)(b + 8)
Cell phone production engineers have noticed that among a group of 138 customers aged 14-23 who send more text messages tend to use a higher percentage of their phone’s memory.What are the explanatory variable and response variable for this relationship?
Explanatory variable: age of customer
Response variable: percentage of phone memory used
Explanatory variable: percentage of phone memory used
Response variable: age of customer
Explanatory variable: number of text messages sent
Response variable: percentage of phone memory used
Explanatory variable: percentage of phone memory used
Response variable: number
Answer:
it is c my guy
Step-by-step explanation:
on edge2020
The explanatory variable is the number of text messages sent, and the response variable is the percentage of phone memory used. The correct answer is (C)
What is the independent and dependent variable?In mathematics, independent and dependent variables are values that vary in relation to one another. The dependent variable is dependent on the independent variable, which means that if the value of the independent variable changes, so will the dependent variable.
In this situation, the explanatory variable is the number of text messages sent, because it is believed to influence or "explain" the variation in the response variable, which is the percentage of phone memory used.
The explanatory variable is also sometimes called the independent variable, because it is the variable that is being manipulated or controlled in an experiment. The response variable is also sometimes called the dependent variable, because it is the variable that is believed to depend on the explanatory variable.
Therefore, in this problem, the explanatory variable is the number of text messages sent, and the response variable is the percentage of phone memory used.
Learn more about the independent and dependent variables here:
https://brainly.com/question/1479694
#SPJ2
One research study of illegal drug use among 12- to 17-year-olds reported a decrease in use (from 11.4% in 1997) to 9.8% now. Suppose a survey in a large high school reveals that, in a random sample of 1046 students, report using illegal drugs. Use a 0.05 significance level to test the principal's claim that illegal drug use in her school is below the current national average.
Using the z-distribution, it is found that since the test statistic is more than the critical value for the left-tailed test, it is found that there is not enough evidence to conclude that illegal drug use in her school is below the current national average.
At the null hypothesis, it is tested if drug use in her school is not below the national average, that is:
[tex]H_0: p \geq 0.098[/tex]
At the alternative hypothesis, it is tested if it is below, that is:
[tex]H_1: p < 0.098[/tex]
The test statistic is given by:
[tex]z = \frac{\overline{p} - p}{\sqrt{\frac{p(1-p)}{n}}}[/tex]
In which:
[tex]\overline{p}[/tex] is the sample proportion. p is the proportion tested at the null hypothesis. n is the sample size.93 out of 1046 reported using illegal drugs, hence the parameters are:
[tex]n = 1046, \overline{p} = \frac{93}{1046} = 0.0889, p = 0.098[/tex]
Hence, the value of the test statistic is:
[tex]z = \frac{\overline{p} - p}{\sqrt{\frac{p(1-p)}{n}}}[/tex]
[tex]z = \frac{0.0889 - 0.098}{\sqrt{\frac{0.098(0.902)}{1046}}}[/tex]
[tex]z = -0.99[/tex]
The critical value for a left-tailed test, as we are testing if the proportion is less than a value, is [tex]z^{\ast} = -1.645[/tex]
Since the test statistic is more than the critical value for the left-tailed test, it is found that there is not enough evidence to conclude that illegal drug use in her school is below the current national average.
To learn more about the use of the z-distribution to test an hypothesis, you can take a look at https://brainly.com/question/25584945
Where did this student make the mistake when solving this inequality?
2x + 4 > 5x - 5
-2x -2x
4 < 3x - 5
+5 +5
9 < 3x
/3 /3 (divide by 3)
3 < x
options:
When subtracting the same value from both sides you don't need to switch the inequality sign
There is no mistake, it was solved correctly
You don't subtract 2x from each side, you add 2x to each side
When dividing by 3 you should switch the inequality sign
Answer:
You don't subtract 2x from each side, you add 2x to each side
2 1/3 divided by 1 1/5 what is the answer as a fraction or mixed number in simplest form?
Answer:
1.9444444 is the answer or 35/18
Step-by-step explanation:
Answer:
10/3 or 3 (1/3)
Step-by-step explanation:
I used a calculator sorry i don't know how to explain it
Which statement is true about the equation 4.5z = 4.5z − 4.25 + 6.25? It has no solution. It has one solution. It has two solutions. It has infinitely many solutions.
Answer:
it has infinitely many solutions
Step-by-step explanation:
hope it help bro
Answer:
d
Step-by-step explanation:
Select the statement that is true.
0.969 < 0.967
0.967 > 0.969
0.967 = 0.969
0.967 < 0.969
Answer:
d option
Step-by-step explanation:
(d) option is true, as 0.969 is greater than 0.967.
Rest all options are false.
Hope it helps :)
A swimming pool already contains
a small amount of water when you start filling it at a
constant rate. The pool contains 45 gallons of water after
5 minutes and 120 gallons after 30 minutes. Find the
average rate of change and use it to write a linear model
that relates the amount of water in the pool to the time.
Answer:
Rate of change = 3 gallons/minute
Starting volume = 30 gallons
Step-by-step explanation:
A graph of the pool's water level would be useful. The slope of the line would represent the rate of change for filling the pool. It will also help us determine the amount of water that was in the pool to start. Although it is tempting to say the rate of fill is 45gallons/5 minutes, or 9 gallons/minute, it is not correct. The pool already started with an unknown volume of water. The rate of change after 5 minutes, however, can be used. The problem states it is being added at a constant rate. Let's find an equation for a line, in the format of y=mx+b, where m is the slope (rate of change) and b is the y-intercept.
We'll let y represent the volume of water in the pool, and x will be the time in minutes. The y-intercept will give us the amount of water in the pool at the start (x = 0).
The slope can be determined between the two given points:
(5,45) and (30,120):
Slope = Rise/Run [The change in y divided by the change in x].
Rise = (120 - 45) = 75
Run = (30-5) = 25
Slope = 75/25 or 3
The line, so far, becomes y=3x + b
The slope of 3 has units of gallons/minute. It is the rate at which the pool is being filled.
We can find b, the starting volume of water, by using one of the two points in the equation and solving for b:
y=3x + b [I'll use (5,45)]
45 = 3*(5) + b
b = 30 gallons
The pool had 30 gallons to start (at x = 0(minutes))
See the graph of the line, attached.
what number could make this equations have no value of x. 3x+8 = 3x + ?
Answer:
All values of x :- 3x + 8 = 3x + 8 has Infinite solutions .Just one value of X :- 3x + 8 = 3x + x is equal to 3x + 8 = 4x , which has one solution at x= 8 .Step-by-step explanation:
I hope this helps you !!Calculate the area of the triangular region determined by the points D(-4,3) E(-7,-8) F(-2, -3)
Answer:
The area is 27
Step-by-step explanation:
Area =1/2 [x1(y2 - y3) + x2(y3 - y1) + x3(y1 - y2)]
Area =1/2 [2(-6 - 8) + 3(8 - 4) + 7(4 + 6)]
=1/2 [2(-14) + 3(4) + 7(10)]
=1/2 (-28 + 12 + 70)
=1/2 (54)
Area = 27
convert NPR 180000 into
1. USD
Answer:
Solution here,
1 US dollar=NRS 120.74
Therefore Rs 180000= 180000/120.74
=$1490.99
PLEASE HELP!! 100 points!!!
The angle of depression from the top of a tower to a boulder on the ground is 22 . If
the tower is 70 feet high, how far from the base of the tower is the boulder? (Round
answer to the 1st decimal place.)
Answer:
173.3 feetStep-by-step explanation:
Let the required distance be x.
We have a right triangle with vertical leg of 70 feet and the acute angle opposite to this leg is 22 degrees.
Use trigonometry:
adjacent / opposite = cotangentx / 70 = cot 22 degx = 70 cot 22 degx = 173.3 feet (rounded)Solve the system of equations
X=11+y
2x+y=19
Answer:
Step-by-step explanation:
To solve this system of equations, let's first find the value y. We can replace the x in the second equation with 11 + y, since we are told in the first equation that x is equal to 11 + y. So, let's replace x:
2(11 + y) + y = 19
22 + 2y + y = 19
22 + 3y = 19
3y = -3
y = -1
And look at that - we've found our y-value! Now, we can replace the y in the first equation with -1 to find the value of x.
x = 11 + (-1)
x = 10
So, the solution to this system of equations is (10, -1). Hopefully that's helpful!
Solve the equation. Please
Answer:
y=3
Step-by-step explanation:
1/4 = 3/12
Derek and Jeannine buy a car for a total price, including tax, of $19,795. The price of the car was $18,500. What is the tax rate.
Answer:1.07
Step-by-step explanation:
Please HELPPP!! Thank you
Answer:
its 6,7 just make it right if im wrong
i need to find the zeros by factoring but im stuck plss help me i think the zeros may be 0, 1, -4, and 4 but i dont know how to get them??
You have 64 inches of blue
fabric and 96 inches of green
fabric. You want to cut the fabric
into pieces of equal length with
no leftovers. What is the greatest
length of the pieces that you can
make?
Answer:
Step-by-step explanation:
48 times for the green fabric
32 for blue
solve the equation 5x+x-7=4x-2-x
Answer:
[tex]x=\frac{5}{3}[/tex]
Step-by-step explanation:
Brainliest pls?
What is an expression equivalent to 25x^2+28x+16
HELLO EVERYONE
WHAT IS THIS ANSWER??? ANYONE KNOW? i need help on this question. it is kinda confusing but if anyone knows pls txt back to this post. thank you so much and have a good day.
Answer: The volume of this cylinder is 2389.18 cubic cm, and the surface area is 1000.6 square cm.
Given this graph of the function f(x) a) b) c) d) please a need help
Answer:
a) 2
b) -2
c) -2
d) 1/2
Step-by-step explanation:
1) f(-4) means that x=-4 and you must locate the y value on the graph
2) f(2) means that x=2 and you must locate the y value on the graph
3) f(x)=4 means that y=4 and you must locate the x value on the graph
4) f(x)=-1 means that y=-1 and you must locate the x value on the graph
what is the greatest common factor of 32 and 56
Solve the following system of equations graphically.
y=3x+4
y=-2x-5
Answer:
(x, y) = (-1.8, -1.4)
Step-by-step explanation:
Someone please help
Based on the information in the table, how much will Henry earn if he worked 7 hours?
A
$48
+
B
$72
С
$9
D
$63
Answer:
D.
Step-by-step explanation:
Solve the literal equation for Y:
4=5x+6y
Answer:
y=2/3-5x/6
Step-by-step explanation:
PLEASE HELP ME 50 POINTSS 1!1!1!1!1!1!1!1!1!11!1!1!1!
How long does it take a baseball moving with an average
speed of 35 m/s to travel 18 m?
What is the average speed of a car that travels 870 km in 14.5
h?
Answer:
1) the baseball will take approx 0.514 seconds to move 18 meters.
35/1 = 18/x
x = 0.514s
2) the car's average speed is 60 km per hour.
870/14.5 = x/1
x = 60h
please Help NEED NOW
thank you so much
−
3
x
+
y
=
−3x+y=
−
3
−3
−
6
x
+
2
y
=
−6x+2y=
−
3
−3
Answer: -3x+4
Step-by-step explanation:
combine like terms.
3x+ -6x=-3
-3+-3+2= -4
-3x + -4
PLEASE NO LINKS AND NO NEGATIVITY
Answer:
8.9k
Step-by-step explanation:
Perimeter is the area around the object.
1.8k - 5 + 3.5 + 6.1k + k + 1.5
Combine like terms:
1.8k + 6.1k + k = 8.9k
-5 + 3.5 + 1.5 = 0
Therefore 8.9k is the answer. You dont need to include the +0 because it will not add anything to the answer. In the most simplified form, the answer is 8.9k
Hope that helps
Answer:
Step-by-step explanation: