9514 1404 393
Answer:
18
Explanation:
Solve the first for a, then substitute into the second.
a = 27/(5b^2)
Then ...
(27/(5b^2))^2·b = 135
27^2/(5^2·135) = b^3 = 27/125
b = ∛(27/125) = 3/5
a = 27/(5(3/5)^2) = 15
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The expression of interest is ...
a +5b = 15 + 5(3/5) = 15 +3
a +5b = 18