Question

Multimea solutiilor ecuatiei 3x la patrat -84=-36 este ...

Answer 1

$3 {x}^{2} - 84 = - 36$

$3 {x}^{2} = - 36 + 84$

$3 {x}^{2} = 48 \: | \div 3$

${x}^{2} = 16$

$x = \pm \sqrt{16}$

$x = \pm4$

$S=\left \{ -4,4 \right \}$

Answer 2

3x²-84=-36

3x²=-36+84

3x²=48

x²=48:3

x²=16

x=+-√16

x=+-4

S={-4;+4}