CPM Homework Help : A2C Problem 11-103

Find the solutions to the system below. The solutions may be real or complex.

$y = x^{2} + 2x + 5 \\y = 2x^{2} + 4x + 7$

Hint:

$−2\left(y = x^{2} + 2x + 5\right) → −2y = −2x^{2} − 4x − 10\\ y = 2x^{2} + 4x + 7$

$−y = −3\\y = 3$

More Help:

Use substitution to find x.

$\left(3\right) = x^{2} + 2x + 5$

0 $= x^{2} + 2x + 2$

Use the quadratic formula.

Answer:

$\left(−1 + i, 3\right) \text{ and } \left(−1 − i, 3\right)$