Question 782059: (Using quadratics to solve)
Jane is 12 times her daughter’s age (x). In 4 years time Jane’s age will be equal to 8 less than the square of her daughter’s age. Find the ages of both Jane and her daughter now?
Answer by algebrahouse.com(1659)   (Show Source):
You can put this solution on YOUR website! x = daughter's age now
12x = Jane's age now
x + 4 = daughter in 4 years
12x + 4 = Jane in 4 years
(x + 4)² - 8 = 12x + 4 {in four years, Jane will be equal to eight less than the square of her daughter}
x² + 8x + 16 - 8 = 12x + 4 {squared the binomial using the foil method}
x² + 8x + 8 = 12x + 4 {combined like terms on left side}
x² - 4x + 4 = 0 {subtracted 12x and 4 from each side}
(x - 2)(x - 2) = 0 {factored into two binomials}
x - 2 = 0 {set the exclusive factor equal to 0}
x = 2 {added 2 to each side}
12x = 24 {substituted 2, in for x, into 12x}
Jane is 24 now
her daughter is 2 now
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