2007-05-02 05:44:26 · 5 answers · asked by weirdo_in_america 1 in Science & Mathematics ➔ Mathematics
sorry i meant 2x^2+60x-2400 = 0
2007-05-02 05:44:52 · update #1
If I'm reading this question correctly, it's +2400 not -2400
That means that the roots are not real.
So the most you can factorize that is taking out the 2.
2(x^2 + 30x + 1200)
That's it.
2007-05-02 06:37:15 · answer #1 · answered by Dr D 7 · 1⤊ 0⤋
Solving by completing the square, since 30 is even:
2x² + 60x + 2400 = 0
x² + 30x = -1200
x² + 30x + 225 = -1200 + 225
(x + 15)² = -975
x + 15 = ±√(-25•39)
x = -15 ± 5i√39
If you tried to factor, you'd only get as far as 2(x² + 30x + 1200) = 0. Since √1200 = 34.64, and 2 of those add up to 68, there will be NO factor pair of 1200 that adds up to only 30.
2007-05-02 06:06:33 · answer #2 · answered by Philo 7 · 1⤊ 0⤋
The factorization is
(x + 15 - 5*sqrt(57))(x + 15 + 5*sqrt(57))
This can be found by solving your equation. First divide everything by 2
x^2 + 30x - 1200 = 0
complete the square
x^2 + 30x + (30/2)^2 = 1200 + 225 = 1425
(x + 15)^2 = 1425
x + 15 = +- 5*sqrt(57)
x = -15 +- 5*sqrt(57)
x + 15 - 5*sqrt(57) = 0 also x + 15 + 5*sqrt(57) = 0
so these are your factors.
2007-05-02 06:05:45 · answer #3 · answered by Anonymous · 0⤊ 0⤋
2x^2+60x-2400 = 0
factor out a 2
x^2+30x-1200 = 0
quad form:
x = -30/2 +- sqrt(900 +4800)/2
x = -15 +- 10sqrt(57)/2
x = -15 +- 5sqrt(57)
2007-05-02 05:47:05 · answer #4 · answered by cat n 3 · 1⤊ 0⤋
Factor out a 2:
2(x^2+30x-1,200)=0
x^2+30x-1,200=0
Use the quadratic formula:
x=-b±√b^2-4ac/2a
a=1,b=30,c=-1,200
x=(-30±√(30)^2-4(1*-1,200))/2(1)
x=(-30±√900-4(-1,200))/2
x=(-30±√900+4,800)/2
x=(-30±√5,700)/2
x=(-30±10√57)/2
x=-15±5√57
x=-52.749 or 22.749
2007-05-02 05:59:17 · answer #5 · answered by Anonymous · 0⤊ 0⤋