The length of
, hypotenuse c = 12, and length a = ?.
Apply pythagorean theorem:
.
(Substitute
, and c = 12)
Evaluate powers:
.

Apply subtraction property of equality: a = b then
.
(Subtract 77 from each side)
Apply commutative property of addition: a + b = b + a.
\
(Apply additive inverse property:
)
(Subtract:
)
Apply square roots property:
then
.
(Evaluate power:
)
The positive value of a = 8.18.
The length of
.