Determine the solutions to the quadratic equation -5x2 + 10x + 15 = 0.

-5x^2 + 10x + 15 = 0; -5(x - 3)(x +1) = 0; -5(x - 3) = 0; -5x + 15 = 0; -5x = -15; x = 3; (x + 1) = 0; x = -1 the solution set is {3, -1}

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Asked 11/6/2013 2:47:40 PM

Updated 6/28/2014 12:00:29 AM

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-5x^2 + 10x + 15 = 0;

-5(x - 3)(x +1) = 0;

-5(x - 3) = 0; -5x + 15 = 0; -5x = -15; x = 3;

(x + 1) = 0; x = -1

the solution set is {3, -1}

-5(x - 3)(x +1) = 0;

-5(x - 3) = 0; -5x + 15 = 0; -5x = -15; x = 3;

(x + 1) = 0; x = -1

the solution set is {3, -1}

Added 6/28/2014 12:00:29 AM

This answer has been confirmed as correct and helpful.

Solve by factoring.
8x2 - 10x - 25 = 0

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Expert Answered

Updated 7/27/2014 3:08:33 PM

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8x^2 - 10x - 25 = 0;

(2x - 5)(4x + 5) = 0;

2x - 5 = 0; x = 5/2;

4x + 5 = 0; x = -5/4

Solutions: x = -5/4 or x = 5/2

(2x - 5)(4x + 5) = 0;

2x - 5 = 0; x = 5/2;

4x + 5 = 0; x = -5/4

Solutions: x = -5/4 or x = 5/2

Added 7/27/2014 3:08:32 PM

This answer has been confirmed as correct and helpful.

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