SOLUTION: How do I solve this quadratic equation, using elimination? x^2+y=8x+19 x^2-y=7x-11 The back of the book says that the answer is (-0.5,14.75) and (8,19) but I do not know how

Algebra ->  Systems-of-equations -> SOLUTION: How do I solve this quadratic equation, using elimination? x^2+y=8x+19 x^2-y=7x-11 The back of the book says that the answer is (-0.5,14.75) and (8,19) but I do not know how       Log On


   



Question 608423: How do I solve this quadratic equation, using elimination?
x^2+y=8x+19
x^2-y=7x-11
The back of the book says that the answer is (-0.5,14.75) and (8,19) but I do not know how they got that.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Just add the two equations just the way they are. The variable will go away. Then collect like terms on one side of the equals sign leaving yourself with a factorable quadratic. Once you have the two roots of the quadratic, substitute back into either of the given equations to determine the value that corresponds to that value. The book's answers are correct.

John

My calculator said it, I believe it, that settles it
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