How do I use the quadratic formula to solve $f (x) = x^{2} + 3 x - 7$ $f(x) = x^2 + 3x - 7$ ?

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Answer 1 · 2014-09-30T03:49:03

$a x^{2} + b x + c = 0$ $ax^2+bx+c=0$

$x^{2} + 3 x - 7 = 0$ $x^2+3x-7=0$

$a = 1, b = 3, c = - 7$ $a=1, b=3, c=-7$

Quadratic formula

$x = \frac{- b \pm \sqrt{b^{2} - 4 a c}}{2 a}$ $x=(-b+-sqrt(b^2-4ac))/(2a)$

$x = \frac{- (3) \pm \sqrt{{(3)}^{2} - 4 (1) (- 7)}}{2 (1)}$ $x=(-(3)+-sqrt((3)^2-4(1)(-7)))/(2(1))$

$x = \frac{- 3 \pm \sqrt{9 + 28}}{2}$ $x=(-3+-sqrt(9+28))/2$

$x = \frac{- 3 \pm \sqrt{37}}{2}$ $x=(-3+-sqrt(37))/2$

How do I use the quadratic formula to solve f(x) = x^2 + 3x - 7f(x)=x2+3x−7f(x) = x^2 + 3x - 7?