Question 400960
Find two numbers whose product is 12 such that one of the numbers is four less than eight times the other number?

x = one number
8x - 4 = other number

x(8x - 4) = 12 {their product is 12}
8x^2 - 4x = 12 {used distributive property}
8x^2 - 4x - 12 = 0 {subtracted 12 from both sides}
4(2x^2 - x - 3) = 0 {factored 4 out}
4(2x - 3)(x + 1) = 0 {factored into two binomials}
2x - 3 = 0 or x + 1 = 0 {set each factor equal to 0}
2x = 3 or x = -1
x = 3/2 or x = -1 {solved each equation for x}
8x - 4 = 8 or 8x - 4 = -12 {substituted into other number}


The numbers are: 3/2 and 8 or -1 and -12
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