A linear equation can be represented by:
y = mx + b
Where m = slope, and b = y intercept.
The slope is a rate of change, so our slope is $150.
The y intercept is the point where the equation crosses the y axis, or the "initial amount" in this case $500.
So our equation will be:
y = 150x + 500.
-5 is for f(x)=x+5
4 is for g(x)=x-4
Hope this helps!!
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