Question

7x²-20x-3=0 quanto é?

Answer 1

$7x {}^{2} - 20x -3 =0$
$7x {}^{2} + x - 21x - 3 = 0$
$x \times (7x + 1) - 3(7x + 1) = 0$
$7x + 1 = 0$
$x - 3 = 0$
$x = - \frac{1}{7}$
$x = 3$
$x1 = - \frac{1}{7}$
$x2 = 3$

Answer 2

7x2+ x- 21x-3=0
X.( 7x+1) -3(7x+1)=0
(7x+1) x (x-3)=0
7x+1=0
x-3=0
x=-1/7
x2=3