Answer:
x =16.8
Step-by-step explanation:
We can use the Pythagorean theorem to find the value of x
a^2 + b^2 = c^2
where 12.6 and x are the legs and 21 is the hypotenuse
12.6 ^2 + x^2 = 21^2
158.76+x^2 = 441
Subtract 158.76 from each side
x^2 = 441- 158.76
x^2=282.24
Take the square root of each side
sqrt(x^2) = sqrt(282.24)
x =16.8
