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If you are solving y 2+2y=48 by completing the square, the next line would be

User Gesellix
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2 Answers

6 votes
What number will make y^2 + 2y + __ a perfect square? Take coefficient of y, divide by 2, then square it = (2/2)^2 = 1 So add 1 to both sides, since y^2 + 2y + 1 = (y + 1)^2 y^2 + 2y + 1 = 49
User Atline
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3 votes

For this case we have the following equation:


y ^ 2 + 2y = 48

By completing squares we have:

Step 1:

Add
(\frac {b} {2}) ^ 2 on both sides:


y ^ 2 + 2y + 1 = 48 + 1

Step 2:

We rewrite the equation:


(y + 1) ^ 2 = 49

Step 3:

We solve the equation:


y = \pm \sqrt {49} -1\\y = \pm7-1

Solutions:


y = 6\\y = -8

Answer:

the next line would be:


y ^ 2 + 2y + 1 = 48 + 1


User Optical Phoenix
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