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8x² + 16x - 62 = -5, solve by completing the square. PLEASE HELP IVE BEEN STRUGGLING FOR HOURS

1 Answer

2 votes

Answer:

x=-1+
(1)/(4)
√(130\\) or x=-1+
(-1)/(4)
√(130)

Step by step:

Step 1: Subtract -5 from both sides.

8x2+16x−62−(−5)=−5−(−5)

8x2+16x−57=0

For this equation: a=8, b=16, c=-57

8x2+16x+−57=0

(plus-minus) = ±

Step 2: Use quadratic formula with a=8, b=16, c=-57.

x=
(-b(plus-minus)√(x) b^2-4ac)/(2a)

x=
(-(16)(plus-minus)√((16)^2-4(8)(-57)) )/(2(8))

x=
(-16(plus-minus) √(2080) )/(16)

ANSWER:

x=-1+
(1)/(4)
√(130) or x=-1+
(-1)/(4)
√(130)

User Iwaduarte
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