Answer:
x = 10 (10.2 or 10.25)
Explanation:
To find the length of the missing side, use the pythagorean theorem. Substitute x and 8 for a and b and 13 for c.
a^2 + b^2 = c^2
(x)^2 + (8)^2 = (13)^2
Evaluate the exponents.
x^2 + 64 = 169
Subtract 64 from both sides.
x^2 = 105
Square root both sides.
x = 10.2469
Round this to the nearest whole number (I'm assuming).
x = 10 (10.2 if rounded to nearest tenth; 10.25 if rounded to the nearest hundredth)