Answer:
First we have the function f(x) = 27*x - 67.5
It has an x-intercept at (a, 0)
This means that:
f(a) = 0 = 27*a - 67.5
Solving the above equation we can find the value of a.
0 = 27*a - 67.5
67.5 = 27*a
67.5/27 = a = 2.5
Now let's look at equation g(x).
It is a linear equation, remember that a linear equation can be written as:
g(x) = y = A*x + B
Where:
A is the slope, and B is the y-intercept.
If the line passes through the points (x₁, y₁) and (x₂. y₂), the slope can be written as:
A = (y₂ - y₁)/(x₂ - x₁)
In this case we can select any two points from the table, for example, I will use the second and third points:
(1, 39) and (2, 32.5)
Then the slope is:
A = (32.5 - 39)/(2 - 1) = -6.5/1 = -6.5
Then the equation is something like:
g(x) = y = -6.5*x + B
B is the y-intercept, to find this value, we can use one of the two points we used before.
For example, (1, 39) means that g(1) = 39
Then:
g(1) = -6.5*1 + B = 39
= B = 39 + 6.5 = 45.5
Then the equation for g(x) is:
g(x) = -6.5*x + 45.5
Now, we know that g(x) has an x-intercept at (b, 0)
this means that:
g(b) = 0 = -6.5*b + 45.5
6.5*b = 45.5
b = 45.5/6.5 = 7
Then the difference between b and a is:
b - a = 7 - 2.5 = 4.5
b is equal to a plus 4.5
And the ratio is:
b/a = 7/2.5 = 2.8
b is 2,8 times larger than a.
