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2 votes
Solve by completing the square. Round
x^2-4x=5

User Rex Low
by
6.0k points

1 Answer

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Answer: -1 and 5.

Explanation:

x - 4x = 5 : Move the constant to the left.

x^2 - 4x - 5 = 0 : Rewrite the expression.

x^2 + x - 5x - 5 = 0 : Factor the expressions.

x(x+1) - 5(x+1) = 0 : Factor the expression.

(x+1)(x-5) = 0 : Seperate into possible cases.

x + 1 = 0, x - 5 = 0 : Solve the equations.

x = -1, x = 5 : The equation has 2 solutions.

User Ikbel
by
6.1k points