Question

If using the method of completing the square to solve the quadratic equation X^2-10x+21=0

Answer 1

X=1/10 (X^2+21)

Hope this helped!

Answer 2

x^2 - 10x + 21 = 0

Add both sides 4

x^2 - 10x + 21 + 4 = 0 + 4

x^2 - 10x + 25 = 4

( x - 5 )^2 = 4

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1 ) x - 5 = 2 ==》 x = 7

2 ) x - 5 = - 2 ==》 x = 3