The problem asks to solve six quadratic equations using the quadratic formula. The equations are: 1) $4n^2 = -12n - 2$ 2) $9p^2 - 24 = -5p$ 3) $-3n^2 + 5n = -14$ 4) $4n^2 + 2n = 9$ 5) $-7r^2 = -12$ 6) $-8r^2 = -7r - 5$

AlgebraQuadratic EquationsQuadratic FormulaSolving Equations
2025/3/7

1. Problem Description

The problem asks to solve six quadratic equations using the quadratic formula. The equations are:
1) 4n2=12n24n^2 = -12n - 2
2) 9p224=5p9p^2 - 24 = -5p
3) 3n2+5n=14-3n^2 + 5n = -14
4) 4n2+2n=94n^2 + 2n = 9
5) 7r2=12-7r^2 = -12
6) 8r2=7r5-8r^2 = -7r - 5

2. Solution Steps

First, we rewrite each equation in the standard quadratic form ax2+bx+c=0ax^2 + bx + c = 0. Then we use the quadratic formula x=b±b24ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} to find the solutions.
1) 4n2=12n24n^2 = -12n - 2
4n2+12n+2=04n^2 + 12n + 2 = 0
a=4,b=12,c=2a = 4, b = 12, c = 2
n=12±1224(4)(2)2(4)n = \frac{-12 \pm \sqrt{12^2 - 4(4)(2)}}{2(4)}
n=12±144328n = \frac{-12 \pm \sqrt{144 - 32}}{8}
n=12±1128n = \frac{-12 \pm \sqrt{112}}{8}
n=12±478n = \frac{-12 \pm 4\sqrt{7}}{8}
n=3±72n = \frac{-3 \pm \sqrt{7}}{2}
2) 9p224=5p9p^2 - 24 = -5p
9p2+5p24=09p^2 + 5p - 24 = 0
a=9,b=5,c=24a = 9, b = 5, c = -24
p=5±524(9)(24)2(9)p = \frac{-5 \pm \sqrt{5^2 - 4(9)(-24)}}{2(9)}
p=5±25+86418p = \frac{-5 \pm \sqrt{25 + 864}}{18}
p=5±88918p = \frac{-5 \pm \sqrt{889}}{18}
3) 3n2+5n=14-3n^2 + 5n = -14
3n2+5n+14=0-3n^2 + 5n + 14 = 0
3n25n14=03n^2 - 5n - 14 = 0
a=3,b=5,c=14a = 3, b = -5, c = -14
n=5±(5)24(3)(14)2(3)n = \frac{5 \pm \sqrt{(-5)^2 - 4(3)(-14)}}{2(3)}
n=5±25+1686n = \frac{5 \pm \sqrt{25 + 168}}{6}
n=5±1936n = \frac{5 \pm \sqrt{193}}{6}
4) 4n2+2n=94n^2 + 2n = 9
4n2+2n9=04n^2 + 2n - 9 = 0
a=4,b=2,c=9a = 4, b = 2, c = -9
n=2±224(4)(9)2(4)n = \frac{-2 \pm \sqrt{2^2 - 4(4)(-9)}}{2(4)}
n=2±4+1448n = \frac{-2 \pm \sqrt{4 + 144}}{8}
n=2±1488n = \frac{-2 \pm \sqrt{148}}{8}
n=2±2378n = \frac{-2 \pm 2\sqrt{37}}{8}
n=1±374n = \frac{-1 \pm \sqrt{37}}{4}
5) 7r2=12-7r^2 = -12
7r2+12=0-7r^2 + 12 = 0
7r212=07r^2 - 12 = 0
a=7,b=0,c=12a = 7, b = 0, c = -12
r=0±024(7)(12)2(7)r = \frac{0 \pm \sqrt{0^2 - 4(7)(-12)}}{2(7)}
r=±33614r = \frac{\pm \sqrt{336}}{14}
r=±42114r = \frac{\pm 4\sqrt{21}}{14}
r=±2217r = \frac{\pm 2\sqrt{21}}{7}
6) 8r2=7r5-8r^2 = -7r - 5
8r2+7r+5=0-8r^2 + 7r + 5 = 0
8r27r5=08r^2 - 7r - 5 = 0
a=8,b=7,c=5a = 8, b = -7, c = -5
r=7±(7)24(8)(5)2(8)r = \frac{7 \pm \sqrt{(-7)^2 - 4(8)(-5)}}{2(8)}
r=7±49+16016r = \frac{7 \pm \sqrt{49 + 160}}{16}
r=7±20916r = \frac{7 \pm \sqrt{209}}{16}

3. Final Answer

1) n=3±72n = \frac{-3 \pm \sqrt{7}}{2}
2) p=5±88918p = \frac{-5 \pm \sqrt{889}}{18}
3) n=5±1936n = \frac{5 \pm \sqrt{193}}{6}
4) n=1±374n = \frac{-1 \pm \sqrt{37}}{4}
5) r=±2217r = \frac{\pm 2\sqrt{21}}{7}
6) r=7±20916r = \frac{7 \pm \sqrt{209}}{16}