Question

Solve the Quadratic

Solve for x.

x^2- x=20

Solution 1:
Solution 2:

Answer 1

Answer:

solution 1: 5

solution 2: -4

Step-by-step explanation:

x²-x-20=0;

(x-5)(x+4)=0;

x₁=5; x₂=-4.

Answer 2

Answer:

Solution 1: $x = 5$

Solution 2: $x = -4$

Step-by-step explanation:

The first is organize the given equation to the next form

$ax^2 + bx + c$

So you substract -20 in both sides of the equation

$x^2 - x - 20 = 0$

Know you can use the quadratic formula or find two number that sum give us $b$ and multiplied $c$.

$b = s + r\\c = sr$

Replacing with the given values we have:

$-1 = s + r\\-20 = sr$

With a trial and error the numbers are -5 and 4. Then you change the equation to

$x^2 - x - 20 = (x - 5)(x + 4)$

And the equation is equal to 0 when  $x$ is equal to 5 and -4.