SOLUTION: f(x)=8x+9; g(x)=7x-5 find (f*g)(x)

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Question 1006554: f(x)=8x+9; g(x)=7x-5
find (f*g)(x)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
(f*g)(x) = f(x) * g(x)
(f*g)(x) = ( f(x) ) * ( g(x) )
(f*g)(x) = ( 8x+9 ) * ( 7x-5 )
(f*g)(x) = 8x( 7x-5 ) + 9( 7x-5 )
(f*g)(x) = 8x(7x)+8x(-5) + 9(7x)+9(-5)
(f*g)(x) = 56x^2-40x+63x-45
(f*g)(x) = 56x^2+23x-45