Solve by completing the square.
y² +10y = -9
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Answer:
y=−1 or y=−9
Step-by-step explanation:
y2+10y=−9
Step 1: Subtract -9 from both sides.
y2+10y−(−9)=−9−(−9)
y2+10y+9=0
Step 2: Factor left side of equation.
(y+1)(y+9)=0
Step 3: Set factors equal to 0.
y+1=0 or y+9=0
y=−1 or y=−9
Answer:
y=−1 or y=−9