SOLUTION: if f(x)=ax^2+2a and f(3)-f(1)=60, what is the value of a?

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Question 682825: if f(x)=ax^2+2a and f(3)-f(1)=60, what is the value of a?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=ax^2+2a

f(3)=a(3)^2+2a

f(3)=a*9+2a

f(3)=9a+2a

f(3)=11a

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f(x)=ax^2+2a

f(1)=a(1)^2+2a

f(1)=a*1+2a

f(1)=1a+2a

f(1)=3a

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f(3)-f(1)=60

11a - 3a = 60

8a = 60

a = 60/8

a = 15/2