SOLUTION: f(x) = 5x/4 + 2/3 What is f(a) if f(a+3)= 5? Please help me

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Question 1065105: f(x) = 5x/4 + 2/3
What is f(a) if f(a+3)= 5?
Please help me
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
f(x) = 5x/4 + 2/3
:
f(a+3) = 5 = (5 * (a+3) / 4) + 2/3
:
12 is our common denominator
:
3 * (5 * (a+3)) + 8 = 5 * 12 = 60
:
15a + 45 + 8 = 60
:
15a = 7
:
a = 7/15
:
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f(a) = 5*(7/15) + 2/3 = 7/3 + 2/3 = 9/3 = 3
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