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1-48.

Solve each of the following quadratic equations. If you need help, refer to the Math Notes box for this lesson.

1. $x^2−8x+15=0$

Factor.

$(x−5)(x−3)=0$

Use the Zero Product Property:
$(x−5)=0(x−3)=0\\ x=5x=3$

$x=\frac{-(-8)\pm\sqrt{(-8)^2-4(1)(15)}}{2(1)}$

$x=\frac{8\pm2}{2}$

$x=5,\,\,\,x=3$

1. $2x^2−5x−6=0$

Notice if you try to factor $2x^2−5x−6$, it doesn't work. Use the Quadratic Formula when that happens.

$x=\frac{5\pm\sqrt{73}}{4}$

$x\approx3.39,\ x\approx-0.89$