Question

i need help with math 1010
completing the square
x^2-9x=10

Answer 1

$x^2-9x=10|+20.25\\ x^2-9x+20.25=30.25\\ (x-4.5)^2=30.25\\ x-4.5=5.5 \vee x-4.5=-5.5\\ x=10 \vee x=-1$