given f(x)=2x-6 and g(x)=9x^2-7x-4.  Find (f*g)(-6).

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 f(x)=2x-6 and g(x)=9x^2-7x-4.  Find (f*g)(-6)

(f*g)(x) = f(g(x)

replace x values in f(x) with g(x)

==> f(g(x)= 2(f(x)) -6

              = 2(9x^2 -7x -4) - 6

               = 18x^2 - 14x -8 -6

               = 18x^2 - 14x -14

==> f*g(x) = 18x^2 -14x - 14

==> f*g(-6) = 18(36) +14(6)...

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 f(x)=2x-6 and g(x)=9x^2-7x-4.  Find (f*g)(-6)

(f*g)(x) = f(g(x)

replace x values in f(x) with g(x)

==> f(g(x)= 2(f(x)) -6

              = 2(9x^2 -7x -4) - 6

               = 18x^2 - 14x -8 -6

               = 18x^2 - 14x -14

==> f*g(x) = 18x^2 -14x - 14

==> f*g(-6) = 18(36) +14(6) -14 = 718

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