SOLUTION: use a quadratic equation to find two real numbers that satisfy each equation for their sum is 7, and their product is 15

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Question 760715: use a quadratic equation to find two real numbers that satisfy each equation for their sum is 7, and their product is 15
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Two numbers, h and k.
hk=15 and h+k=7

h=7-k, substitute into the 15 equation.
%28h%29k=15
%287-k%29k=15
7k-k%5E2=15
-k%5E2%2B7k-15=0
k%5E2-7k%2B15=0 which would have been what lead to your question. Use the general solution to a quadratic equation.

k=%287%2B-+sqrt%2849-4%2A15%29%29%2F2
k=%287%2B-+sqrt%28-11%29%29%2F2
NO REAL SOLUTION