SOLUTION: Solve each quadratic equation by completing the square 1. x2 - 3x - 1 (x is base,2 is the exponent) 2. x2 - 14x + 13 = 0 (x is base,2 is the exponent)

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Question 1040729: Solve each quadratic equation by completing the square
1. x2 - 3x - 1
(x is base,2 is the exponent)
2. x2 - 14x + 13 = 0
(x is base,2 is the exponent)
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Solve each quadratic equation by completing the square
1. x^2 - 3x - 1 = 0
x^2 - 3x + __ = 1
Find the value that completes the square: Half the cofficient of x squared
That is -1.5^2 = 2.25, add this to both sides
x^2 - 3x + 2.25 = 1 + 2.25
x^2 - 3x + 2.25 = 3.25
which is
(x-1.5)^2 = 3.25
Find the square root of both sides
x - 1.5 = +/-sqrt%283.25%29
Two solutions
x = 1.5+%2B+sqrt%283.25%29
and
x = 1.5+-+sqrt%283.25%29
:
2. x^2 - 14x + 13 = 0
x^2 - 14x + ___ = - 13
-7^2 = 49, add to both sides
x^2 - 14x + 49 = -13 + 49
x^2 - 14x + 49 = 36
(x - 7)^2 = 36
x - 7 = +/-sqrt%2836%29
two solutions
x = 7 + 6
x = 13
and
x = 7 - 6
x = 1