Answer:
The plan is:
A fixed cost of $50 per month.
An extra of $15 per GB used over the limit of 2B.
We can write this as a linear equation:
C(x) = $15*x + $50
C(x) is the monthly cost, and x is the number of GB that she used over the limit.
Then, if she used 3GB over the limit, we should replace x by 3.
C(3) = $15*3 + $50 = $45 + $50 = $95.
And the answer to the second question was already found, if she used xx GB in the month, then we have:
C(xx) = $15*xx + $50
(we replaced the x in the general equation by xx)
Let's begin by calling Sarah's age now as X. As Ralph is 3 times as old as Sarah, X times 3 = 3X. Hence, Ralph's age is 3X. In six years, Ralph will be twice as old as Sarah. To calculate six years from now, add 6 to X for Sarah, and 6 to 3X for Ralph. As Ralph is twice as old as Sarah and we want to find the difference between the ages to calculate X, multiply X+6 by 2. You'll get 2X+12. Therefore, 2X+12=3X+6. Deduct 6 from 3X+6 as we want to isolate the variable. Because you did that to one side, you have to deduct 6 from 2X+12. Hence, now you have 2X+6=3X. X=6. Ralph's age is 3X, so 6 times 3 is 18. Ralph is 18 years old.
<u>Answer:</u>
8
<u>Step-by-step explanation:</u>
We are given the following expression and we are to find the simplest form of this expression:

First of all, we will factor the coefficient:

Rewriting it as:

Applying the exponent rule
to get:


Option C:
The equation which matches the graph above is y = 4x - 4.
Solution:
Take any two points on the graph of the line.
Let the points are (0, -4) and (1, 0).
Here, 
Slope of the line:



m = 4
y-intercept of the line is the point where the line crosses at y-axis.
Here, the line crosses at y-axis is (0, -4).
y-intercept, (c) = -4
Equation of a line is
y = mx + c
y = 4x + (-4)
y = 4x - 4
The equation which matches the graph above is y = 4x - 4.
Option C is the correct answer.