Question

calcule o valor de a:

Answer 1

$\alpha^2 = h^2 - Co^2 \\ \\ \alpha^2 = 21^2 - (7,5)^2 \\ \\ \alpha^2 = 441 - 56,25 \\ \\ \alpha^2 = 384,75 \\ \\ \alpha = \sqrt{384,75} \\ \\ \alpha \approx 19,61$

Answer 2

21²= 7,5²+a²

441= 56,25 + a²

441-56,25= a²

a²=384,75

a=√384,75

a= 19,61