sqrt(x-4)+sqrt(x+24)=14
sqrt-корень

ОДЗ  х-4>0 U x+24>0⇒x>4 U x>-24⇒x∈(4;≈)
x-4+2√(x-4)(x+24) +x +24=196
2√(x-4)(x+24)=176-2x
√(x-4)(x+24)=88-x
(x-4)(x+24)=(88-x)²
x²+24x-4x-96-7744+176x-x²=0
200x=7840
x=39,2