Question

Me ajudem a resolver isso:
10²=x²+3x²

Answer 1

10²=x²+3x²
100 = x²+3x²
- x²-3x² = - 100
- 4x² = - 100 . (-1)
4x² = 100
x² = 100/4
x = +- √ 100/4
x = +- 10/2
x = +- 5

S = { 5 ; - 5 }