Question

Hallar "x":

5²= (√21)² + x²

Answer 1

5²= (√21)² + x²
25 = (3)² + x²
25 = 9 + x²
25-9 = x²
16 = x²
√16 = x
4 = x

Answer 2

${5}^{2} = {(\sqrt{21})}^{2} + {x}^{2} \\ 25 = 21 + {x}^{2} \\ 25 - 21 = {x}^{2} \\ 4 = {x}^{2} \\ \sqrt{4} = \sqrt{ {x}^{2} } \\ 2 = x$