dimitri is solving the equation $x^2 - 10x = 21$. which value must be added to both sides of the equation to…

dimitri is solving the equation $x^2 - 10x = 21$. which value must be added to both sides of the equation to make the left side a perfect-square trinomial?\n0\n4\n25\n100
Answer
Explanation:
Step1: Identify coefficient of x
The coefficient of $x$ is $-10$.
Step2: Take half of the coefficient
$\frac{-10}{2} = -5$
Step3: Square the result
$(-5)^2 = 25$
Answer:
C. 25