SOLUTION: The function g is defined by g(x)=3x^2-4x. Find g(5x)

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Question 1040459: The function g is defined by g(x)=3x^2-4x.
Find g(5x)
Found 2 solutions by jim_thompson5910, josgarithmetic:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
g%28x%29=3x%5E2-4x


g%285x%29=3%285x%29%5E2-4%285x%29 Replace every copy of 'x' with '5x'


g%285x%29=3%2825x%5E2%29-4%285x%29


g%285x%29=75x%5E2-20x

Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
x in the defined function is a dummy variable. You could call it r if you wish to, and say, g%28r%29=3r%5E2-4r.

Next, you want to find what is g(5x), in which r=5x.
g%285x%29=3%285x%29%5E2-4%285x%29
highlight%2875x%5E2-20x%29