How do you solve using the quadratic formula $x^2-3x=-10$ ?

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Answer 1 · 2018-03-09T03:09:34

See a solution process below:

First, add $color(red)(10)$ to each side of the equation to put the equation in standard form:

$x^2 - 3x + color(red)(10) = -10 + color(red)(10)$

$x^2 - 3x + 10 = 0$

We can use the quadratic equation to solve this problem:

For $color(red)(a)x^2 + color(blue)(b)x + color(green)(c) = 0$ , the values of $x$ which are the solutions to the equation are given by:

$x = (-color(blue)(b) +- sqrt(color(blue)(b)^2 - (4color(red)(a)color(green)(c))))/(2 * color(red)(a))$

Substituting:

$color(red)(1)$ for $color(red)(a)$

$color(blue)(-3)$ for $color(blue)(b)$

$color(green)(10)$ for $color(green)(c)$ gives:

$x = (-color(blue)(-3) +- sqrt(color(blue)(-3)^2 - (4 * color(red)(1) * color(green)(10))))/(2 * color(red)(1))$

$x = (3 +- sqrt(9 - 40))/2$

$x = (3 +- sqrt(-31))/2$

How do you solve using the quadratic formula x^2-3x=-10x^2-3x=-10?