SOLUTION: what two numbers multiplied together gives me a negative 2 but added together give me a negative 5

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Question 306397: what two numbers multiplied together gives me a negative 2 but added together give me a negative 5
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.AB=-2
2.A%2BB=-5
From eq. 1,
AB=-2
A=-2%2FB
Substitute in eq. 2,
A%2BB=-5
-2%2FB%2BB=-5
-2%2BB%5E2=-5B
B%5E2-5B-2=0
Use the quadratic formula,
B+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
B+=+%28-%28-5%29+%2B-+sqrt%28+5%5E2-4%2A1%2A%28-2%29+%29%29%2F%282%2A1%29+
B+=+%285%2B-+sqrt%28+25%2B8+%29%29%2F%282%29+
highlight_green%28+B+=+%285%2B-+sqrt%28+33+%29%29%2F%282%29+%29
From that then,
A=-2%2FB
highlight_green%28A=-1%2F%285+%2B-+sqrt%2833%29%29%29
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I leave it to you to solve for A and B and verify that they do solve the two equations.