Question

Rhett is solving the quadratic equation zero equals X2 minus 2X -3 using the quadratic formula which shows the correct substitution of the value of a a,b and c into the quadratic formula

Answer 1

x^2-2x -3 =0
a =1 b =-2 and c = -3

x = - (-2) +/- sqrt (-2)^2 - 4(1)(-3)
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2(1)

x = + 2 +/- sqrt [(4) - 4(-3)]
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2

x = +2 +/- sqrt [4 + 12]
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2
x = +2 +/- sqrt[16]
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2

x = +2 +/- (4)
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2

x = 2 + 4 or 2 -4
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2 2

x = 6/2 or -2/2

x = 3 or x = -1