## youngstar10 one year ago What number must you add to complete the square? x2 + 14x = -7 A. 196 B. 49 C. 7 D. 14

1. myininaya

$x^2+bx+(b/2)^2=(x+b/2)^2$

2. myininaya

so add to both sides $(b/2)^2$ can you guess what b should be?

3. youngstar10

14x ?

4. myininaya

well b is just the 14 bx is 14x but our formula calls for just b which is 14

5. myininaya

so plug 14 into that (b/2)^2 thing to figure out your answer as to what to add to both sides in order to complete the square

6. youngstar10

oh 196

7. myininaya

no

8. myininaya

$(\frac{14}{2})^2$ what is 14/2?

9. youngstar10

7 so the answer would be 49

10. myininaya

$(\frac{14}{2})^2=(7)^2=49$ right