I need help with the following problem. I forgot how to do these and this assignment is due tomorrow. Any help would be greatly appreciated!

Solve by substitution method:

x + y = 2

y = x^2 - 4

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- Dec 7th 2009, 08:06 PMiDrumSolving simultaneous equations using substitution method.
I need help with the following problem. I forgot how to do these and this assignment is due tomorrow. Any help would be greatly appreciated!

**Solve by substitution method:**

**x + y = 2**

**y = x^2 - 4** - Dec 7th 2009, 08:22 PMBacterius
Substitute the second one into the first one. Thus, you get :

$\displaystyle x + (x^2 - 4) = 2$

$\displaystyle x + x^2 = 6$

$\displaystyle x^2 + x - 6 = 0$

Now solve for $\displaystyle x$ using the factorization method or the quadratic formula, then substitute back the $\displaystyle x$'s into the first equation to find the $\displaystyle y$'s (Nod) - Dec 7th 2009, 08:36 PMiDrum
Thanks alot. Got it now. =]