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What is true about the solution of -8/2y-8=5/y+4-7y+8/y²-16?

A. Y = –4
B. y = –2
C. y = 4
D. y = 6

User Ugoren
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1 Answer

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Final answer:

To solve the given equation, we simplify it by multiplying both sides by (y+4)(y-4), cancel out common terms, distribute, combine like terms, move all terms to one side, factor the quadratic equation, and solve for y. The solutions are y = -2.25 and y = 6. None of the given options A, B, C, or D are true.

Step-by-step explanation:

To solve the given equation, -8/2y-8=5/y+4-7y+8/y²-16, we need to simplify the equation first. Multiplying both sides of the equation by (y+4)(y-4) will help us eliminate the denominator.

Multiply the entire equation by (y+4)(y-4): (y+4)(y-4)(-8/2y-8) = (y+4)(y-4)(5/y+4-7y+8/y²-16)

Simplify both sides of the equation:

On the left side, we can cancel out (y+4) in the denominator: -8(y-4) = 5(y+4-7y+8)/(y-4)(y+4)

On the right side, we can simplify the expression: (y+4-7y+8) = 5(y+4)/(y-4)

Distribute and simplify further:

On the left side, distribute -8 to (y-4): -8y + 32 = (y+4)/(y-4)

On the right side, distribute 5 to (y+4): (5y + 20)/(y-4)

Combine like terms: -8y + 32 = (5y + 20)/(y-4)

Multiply both sides by (y-4) to eliminate the fraction: (y-4)(-8y + 32) = (5y + 20)

Expand and simplify: -8y^2 + 32y - 4(-8y) + 4(32) = 5y + 20

Combine like terms: -8y^2 + 32y + 32y + 128 = 5y + 20

Combine like terms: -8y^2 + 64y + 128 = 5y + 20

Moving all terms to one side: -8y^2 + 64y + 128 - 5y - 20 = 0

Combine like terms: -8y^2 + 59y + 108 = 0

Factor the quadratic equation: (4y + 9)(-2y + 12) = 0

Set each factor equal to zero: 4y + 9 = 0 or -2y + 12 = 0

Solve for y:

For 4y + 9 = 0: 4y = -9, y = -9/4, y = -2.25

For -2y + 12 = 0: -2y = -12, y = -12/-2, y = 6

Therefore, the solutions for the given equation are y = -2.25 and y = 6. None of the options A, B, C, or D are true.

User Andrew Arrow
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