Question

Hi I really need help with this question please,

Answer 1

`{ ( √(30 - x) )}^(2) = {x}^(2) \\ 30 - x = {x}^(2) \\ \\ {x}^(2) + x - 30 = 0 \\ delta = 1 - 4 * ( - 30) * 1 = 121 \\ x1 = ( - 1 + √(121) )/(2 * 1) = ( - 1 + 11)/(2) = 5 \\ x2 = ( - 1 - √(121) )/(2 * 1) = ( - 1 - 11)/(2) = - 6 \\`