How do you solve $7 x^{2} - 10 x = - 3$ $7x ^ { 2} - 10x = - 3$ ?

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Answer 1 · 2017-03-03T17:20:40

$x = 1$ $x=1$

$7 x^{2} - 10 x = - 3$ $7x^2-10x=-3$

$7 x^{2} - 10 x + 3 = 0$ $7x^2-10x+3=0$

$(7 x - 3) (x - 1) = 0$ $(7x-3)(x-1)=0$

$7 x - 3 = 0$ $7x-3=0$ or $x - 1 = 0$ $x-1=0$

$7 x = 3$ $7x=3$ or $x = 1$ $x=1$

$x = \frac{3}{7}$ $x=3/7$ or $x = 1$ $x=1$

substitute x=3/7

$7 {(\frac{3}{7})}^{2} - 10 (\frac{3}{7}) = - 3$ $7(3/7)^2-10(3/7)=-3$

$7 (\frac{9}{7}) - \frac{30}{7} = - 3$ $7(9/7)-30/7=-3$

$\frac{63}{7} - \frac{30}{7} = - 3$ $63/7-30/7=-3$

$\frac{33}{7} = - 3$ $33/7=-3$

$4 \frac{4}{7} = - 3$ $4 4/7=-3$

$x = \frac{3}{7}$ $x=3/7$ = Extraneous solution

substitute $x = 1$ $x=1$

$7 {(1)}^{2} - 10 (1) = - 3$ $7(1)^2-10(1)=-3$

$7 - 10 = - 3$ $7-10=-3$

$- 3 = - 3$ $-3=-3$

$:.x=1$

How do you solve 7x ^ { 2} - 10x = - 37x2−10x=−37x ^ { 2} - 10x = - 3?