How do you solve $4x^2 – 12x = -9$ ?

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Answer 1 · 2015-09-14T06:10:14

$color(blue)(x=3/2$

$4x^2–12x+9=0$

The equation is of the form $color(blue)(ax^2+bx+c=0$ where:
$a=4, b=-12, c=9$

The Discriminant is given by:
$color(blue)(Delta=b^2-4*a*c$
$= (-12)^2-(4*4*9)$
$= 144-144=0$

As $Delta=0$ there is only one solution.

The solution is found using the formula
$x=(-b+-sqrtDelta)/(2*a)$

$x = (-(-12)+-sqrt(0))/(2*4) = (12+0)/8 = 12/8 = 3/2$

The solution is
$color(blue)(x=3/2$

How do you solve 4x^2 – 12x = -94x^2 – 12x = -9?