Factor x 2 – 8 x + 15. Which pair of numbers has a product of ac and a sum of b?

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Factor       x    2    –  8  x  +  15. Which pair of numbers has a product of ac and a sum of b?

Zaria Tanner · Accepted Answer

The pair of numbers that has a product of ac and a sum of b is   (  x  −  5  )  (  x  −  3  )What is a quadratic equation?A quadratic equation is used for the expression of algebraic terms in their second degree. It is used written in the form:  a      x    2    +  b  x  +  c  =  0From the given  information:      x    2    −  8  x  +  15  =  0where;a = 1b =  - 8c = 15To determine the product of ac and the sum of b;We will look for two values that when we multiply them together, we will have +15 and when we add them together we will have -8.The two values are -3 and - 5The product of -3 and - 15 is ac = +15The sum of -3 and -5 is b = -8Now, the quadratic equation becomes:      x    2    −  3  x  −  5  x  +  15  =  0    x  (  x  −  3  )  −  5  (  x  −  3  )  =  0    (  x  −  5  )  (  x  −  3  )  =  0

Factor x^2 – 8x + 15. Which pair of numbers has a product of ac and a sum of b?

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