Question

What number must you add to complete square?

Answer 1

To complete the square you take the coefficient of the 'b' term (10), divide it by 2 (10/2), then square it (5^2 = 25). This is the number you add.
Letter C 25

Answer 2

Answer:

Option C is correct.

A number is, 25

Step-by-step explanation:

To complete the square of the given equation: $x^2+10x = 8$

Take half of the value of the term containing x then square it,

and add and subtract that value from the left-hand side of the equation.

It should be done in the following manner:

$x^2+10x+(5)^2- (5)^2= 8$

Now, use the middle-term break to factories the expression within the parenthesis,

$(x^2+10x+5^2)-25= 8$

Use the algebraic identity: $(a+b)^2 = a^2+2ab+b^2$

we have;

$(x+5)^2 -25=8$

Add 25 to both sides we get;

$(x+5)^2=33$

Therefore, you add a number 25  to complete the square.