If f(x)=x^2 and g(x)=4f(x)-1, then what is the value of g(-3)? i don't get

The answer is 35.

For g(-3), we substitute -3 for x:

g(-3) = 4f(-3) - 1

Since f(x) = x², this means that
f(-3) = (-3)² = 9; we can put this in place of f(-3):

g(-3) = 4(9) - 1
g(-3) = 36 - 1 = 35

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