solve equation algebraically, check all solutions

y=x squared - x

x+y=4

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- Dec 1st 2007, 06:57 PMblame_canada100linear quadratic equation
solve equation algebraically, check all solutions

y=x squared - x

x+y=4 - Dec 1st 2007, 07:01 PMJhevon
you mean, solve the system of equations...

from the second equation, we see that $\displaystyle y = 4 - x$, plug this into the first equation, we get

$\displaystyle 4 - x = x^2 - x$

now continue. solve for all the values of $\displaystyle x$ and then plug them into $\displaystyle y = 4 - x$ to find the corresponding values for $\displaystyle y$ - Dec 1st 2007, 07:04 PMOzzMan
I got x + (x^2 - x) = 4

x^2 = 4

x = 2 or -2

2 + y = 4

y = 2

-2 + y = 4

y = 6

When x is 2 y is 2, when x is -2 y is 6

(2,2) (-2,6) or the possible solutions