SOLUTION: the difference between two numbers is 3.If the square of the smaller number is equal to 4 times the larger number, find the numbers.

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Question 892479: the difference between two numbers is 3.If the square of the smaller number is equal to 4 times the larger number, find the numbers.

Answer by algebrahouse.com(1659) About Me  (Show Source):
You can put this solution on YOUR website!
x = larger number
y = smaller number

x - y = 3 {difference between two numbers is 3
y² = 4x {square of smaller is equal to 4 times the larger

y = x - 3 {added y to each side in top original equation}

(x - 3)² = 4x {substituted (x - 3), in for y, into bottom original equation}
x² - 6x + 9 = 4x {squared the binomial by multiplying by itself}
x² - 10x + 9 = 0 {subtracted 4x from each side}
(x - 9)(x - 1) = 0 {factored into two binomials}
x - 9 = 0 or x - 1 = 0 {set each factor equal to 0}
x = 9 or x = 1 {solved each equation for x}

y = x - 3
y = 9 - 3 or y = 1 - 3 {substituted 9 and 1 for x into y = x - 3}
y = 6 or y = -2

9 and 6
or
1 and -2 are the sets of numbers

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