130k views
1 vote
If using the method of completing the square to solve the quadratic equation x^2 - 15x - 10 = 0, which number would have to be added to "complete the square"?

1 Answer

5 votes

x^2-15x-10=0

Completing the square method:


ax^2+bx+c=0

1. Move the constants to one side. Move the constant term c to the right side of the equation:


x^2-15x=10

2. Add (b/2)^2 to both sides:

Find (b/2)^2:


(-(15)/(2))^2=(225)/(4)
\begin{gathered} x^2-15x+(225)/(4)=10+(225)/(4) \\ \\ x^2-15x+(225)/(4)=(265)/(4) \\ \end{gathered}The number you need to add in both sides of the equation to complete the square is 225/4

3. Factor and solve

User Desert Ice
by
7.6k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories