How do you solve $(r+7)^(3/2) = 729$ ?

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Answer 1 · 2016-01-25T07:15:01

Step by step working is shown below.

$(r+7)^(3/2) = 729$

To solve we can square both sides, this would remove the radical.

$(r+7)^3 = 729^2$

$(r+7)^3 = (9^3)^2$

$(r+7)^3 = (9^2)^3$

Now take cube root on both the sides.

$root(3)((r+7))^3 = root(3)((9^2))^3$

$r+7 = 9^2$

$r+7 = 81$

$r=81-7$

$r=74$

How do you solve (r+7)^(3/2) = 729(r+7)^(3/2) = 729?