Answer:
9x² - 54x + 79
Step-by-step explanation:
To find (f ○ g)(x) substitute x = g(x) into f(x), that is
f(g(x))
= f(3x - 7)
= (3x - 7)² - 4(3x - 7) + 2 ← expand factor using FOIL
= 9x² - 42x + 49 - 12x + 28 + 2 ← collect like terms
= 9x² - 54x + 79
Let the width be 2w. Then the lenght is 5w. So:
(2w)(5w)=490
10w²=490
w²=49
w=±7
So, 2w=width=14 in; and 5w=length=35 in
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