Question

Rewrite the equation by completing the square. x^2-x-20=0

Answer 1

Step-by-step explanation:

${x}^{2} - x + \frac{ 1}{4} = 20 + \frac{1}{4} \\ {(x - \frac{1}{2} )}^{2} = \frac{81}{4} \\ {(x - \frac{1}{2} )}^{2} = {( \frac{9}{2} )}^{2} \\x - \frac{1}{2} = \frac{9}{2} \\ x = \frac{10}{2} = 5 \\ </p><p>x - \frac{1}{2} = - \frac{9}{2} \\ x = - \frac{9}{2} + \frac{1}{2} = - \frac{8}{2} = - 4$