You can put this solution on YOUR website! solve the equation by completing the square: 4x^2 + 40x + 280 = 0
4x^2 + 40x + ___ = -280
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Divide both sides by 4
x^2 + 10x + ____ = -70
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Find the value of the 3rd term that completes the square
using the coefficient of x: (10/2)^2 = 25
x^2 + 10x + 25 = -70 + 25
:
x^2 + 10x + 25 = -45
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Which is:
(x + 5)^2 = -45
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Find the square root of both sides
x + 5 = +/-
:
x + 5 = +/-
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Extract the square root of -1 and 9
x + 5 = +/-
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Two solutions
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