Question

qual é a resoluçao de 2x²-90=8

Answer 1

2x²-90⇒8
2x²⇒8+90
2x²⇒98
x²⇒98/2
x²⇒49
x⇒√49
x⇒+/-7
sendo x⇒+7ou-7

Answer 2

$2x^{2} -90=8 \\ 2x^{2} = 8 +90 \\ 2x^{2} = 98 \\ x^{2} = \frac{98}{2} \\ x^{2}= 49 \\ x= +- \sqrt{49} \\ x=+-7$