A. (f + g)(x) = f(x) + g(x) = 4x - 5 + 3x + 9 = 7x + 4
B. f.g (x) = f(x) * g(x) = (4x - 5)*(3x + 9) = 12x^2 + 36x - 15x - 45
= 12x^2 + 21x - 45
C Replace the x in f(x) by g(x):-
= 4(3x + 9) - 5
= 12x + 36 - 5
= 12x + 31
Answer:
See explanation below.
Step-by-step explanation:
Let's say,
x = number of tokens required to play one game of ping pong
y = number of token required play one game of pinball
Using the data given, the system of equations are:

Solving the system of equations using substitution method will give us:

So, one game of ping pong required 1 token, whereas one game of pinball required 4 tokens.
You would add up all of the sides by combining like terms. Let me know if you want the answers for it.
The linear equation that has a slope of -7 and crosses the x-axis at (3, 0) is:
y = -7x + 21
<h3>
How to find the linear equation?</h3>
A general linear equation is:
y = a*x +b
Where a is the slope and b is the y-intercept.
The slope must be equal to the limit found in part a, and you say that it is equal to -7, so the slope is -7. And for how is written the problem, I understand that it crosses the x-axis at x = 3.
Then we will have:
y = -7*x + b
Such that, when x = 3, y = 0, then:
0 = -7*3 + b
21 = b
Then the linear equation is y = -7x + 21
If you want to learn more about linear equations:
brainly.com/question/1884491
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