Question

Solve b2 + 8b – 30 = 3 by completing the square

Answer 1

i'm not quite sure how to do this :/

Answer 2

is there multiple choice?

Answer 3

\[\Large b^2 + 8b - 30 = 3\]


\[\Large b^2 + 8b = 3+30\]


\[\Large b^2 + 8b = 33\]


\[\Large b^2 + 8b+16 = 33+16\]


\[\Large (b+4)^2 = 49\]


See where to go from here?

Answer 4

In the second to the last step I took half of 8 to get 4. Then squared 4 to get 16. From there, I added 16 to both sides.

Answer 5

Keep going to get

\[\Large (b+4)^2 = 49\]

\[\Large b+4 = \pm\sqrt{49}\]

\[\Large b+4 = \sqrt{49} \ \text{or} \ b+4 = -\sqrt{49}\]

\[\Large b+4 = 7 \ \text{or} \ b+4 = -7\]

\[\Large b = -4+7 \ \text{or} \ b = -4-7\]

\[\Large b = 3 \ \text{or} \ b = -11\]