Question

Tìm x :

x² - 10x = -25

Answer 1

Ta có : x² - 10x = -25

=> x² - 2.x.5 + 5² = 0

<=> (x - 5)² = 0

=> x - 5 = 0

=> x = 5 

Answer 2

x²-10x = -25
=> x² -10x +25=0
=> (x-5)² = 0
=> x = 5

Answer 3

\(x^2-10x=-25\)

\(\Leftrightarrow x^2-10x+25=0\)

\(\Leftrightarrow x^2-2.5.x+5^2=0\)

\(\Leftrightarrow\left(x-5\right)^2=0\)

\(\Rightarrow x=5\)