Question

Eu quero passo a passo dessa equação -3x²-21x-36=0

Answer 1

-3x² -21x -36=0 ===> :(-3) ↓

x² +7x + 12=0 => a=1....b=7....c=12

∆= b² -4.a.c = (7)² -4.1.12= 49 -48 = 1

x = -b±√∆/2a

x = -7±1/2

x' = -7+1/2 = -6/2 = -3 ✓

x" = -7-1/2 = -8/2 = -4 ✓

Answer 2

-3x² - 21x -36 = 0 (÷-3)

x² + 7x + 12 = 0

∆ = 7² - 4.1.12

∆ = 49 - 48

∆ = 1

$x = \frac{ - 7 + - \sqrt{1} }{2 \times 1}$

$x = \frac{ - 7 + - 1}{2}$

$x1 = \frac{ - 7 + 1}{2} = - 3 \\ x2 = \frac{ - 7 - 1}{2} = - 4$