Answer:
a = 32
Step-by-step explanation:
This is a right triangle and the square value of hypotenuse is equal to sum of square value of other two side lengths
68^2 = 60^2 + a^2
4624 = 3600 + a^2
4624 - 3600 = a^2
1024 = a^2 find the root for both sides
32 = a
