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a+b=50 ab=-30000
To solve the equation, factor x^{2}+50x-30000 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
-1,30000 -2,15000 -3,10000 -4,7500 -5,6000 -6,5000 -8,3750 -10,3000 -12,2500 -15,2000 -16,1875 -20,1500 -24,1250 -25,1200 -30,1000 -40,750 -48,625 -50,600 -60,500 -75,400 -80,375 -100,300 -120,250 -125,240 -150,200
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -30000.
-1+30000=29999 -2+15000=14998 -3+10000=9997 -4+7500=7496 -5+6000=5995 -6+5000=4994 -8+3750=3742 -10+3000=2990 -12+2500=2488 -15+2000=1985 -16+1875=1859 -20+1500=1480 -24+1250=1226 -25+1200=1175 -30+1000=970 -40+750=710 -48+625=577 -50+600=550 -60+500=440 -75+400=325 -80+375=295 -100+300=200 -120+250=130 -125+240=115 -150+200=50
Calculate the sum for each pair.
a=-150 b=200
The solution is the pair that gives sum 50.
\left(x-150\right)\left(x+200\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=150 x=-200
To find equation solutions, solve x-150=0 and x+200=0.
a+b=50 ab=1\left(-30000\right)=-30000
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-30000. To find a and b, set up a system to be solved.
-1,30000 -2,15000 -3,10000 -4,7500 -5,6000 -6,5000 -8,3750 -10,3000 -12,2500 -15,2000 -16,1875 -20,1500 -24,1250 -25,1200 -30,1000 -40,750 -48,625 -50,600 -60,500 -75,400 -80,375 -100,300 -120,250 -125,240 -150,200
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -30000.
-1+30000=29999 -2+15000=14998 -3+10000=9997 -4+7500=7496 -5+6000=5995 -6+5000=4994 -8+3750=3742 -10+3000=2990 -12+2500=2488 -15+2000=1985 -16+1875=1859 -20+1500=1480 -24+1250=1226 -25+1200=1175 -30+1000=970 -40+750=710 -48+625=577 -50+600=550 -60+500=440 -75+400=325 -80+375=295 -100+300=200 -120+250=130 -125+240=115 -150+200=50
Calculate the sum for each pair.
a=-150 b=200
The solution is the pair that gives sum 50.
\left(x^{2}-150x\right)+\left(200x-30000\right)
Rewrite x^{2}+50x-30000 as \left(x^{2}-150x\right)+\left(200x-30000\right).
x\left(x-150\right)+200\left(x-150\right)
Factor out x in the first and 200 in the second group.
\left(x-150\right)\left(x+200\right)
Factor out common term x-150 by using distributive property.
x=150 x=-200
To find equation solutions, solve x-150=0 and x+200=0.
x^{2}+50x-30000=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-50±\sqrt{50^{2}-4\left(-30000\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 50 for b, and -30000 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-50±\sqrt{2500-4\left(-30000\right)}}{2}
Square 50.
x=\frac{-50±\sqrt{2500+120000}}{2}
Multiply -4 times -30000.
x=\frac{-50±\sqrt{122500}}{2}
Add 2500 to 120000.
x=\frac{-50±350}{2}
Take the square root of 122500.
x=\frac{300}{2}
Now solve the equation x=\frac{-50±350}{2} when ± is plus. Add -50 to 350.
x=150
Divide 300 by 2.
x=-\frac{400}{2}
Now solve the equation x=\frac{-50±350}{2} when ± is minus. Subtract 350 from -50.
x=-200
Divide -400 by 2.
x=150 x=-200
The equation is now solved.
x^{2}+50x-30000=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
x^{2}+50x-30000-\left(-30000\right)=-\left(-30000\right)
Add 30000 to both sides of the equation.
x^{2}+50x=-\left(-30000\right)
Subtracting -30000 from itself leaves 0.
x^{2}+50x=30000
Subtract -30000 from 0.
x^{2}+50x+25^{2}=30000+25^{2}
Divide 50, the coefficient of the x term, by 2 to get 25. Then add the square of 25 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+50x+625=30000+625
Square 25.
x^{2}+50x+625=30625
Add 30000 to 625.
\left(x+25\right)^{2}=30625
Factor x^{2}+50x+625. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x+25\right)^{2}}=\sqrt{30625}
Take the square root of both sides of the equation.
x+25=175 x+25=-175
Simplify.
x=150 x=-200
Subtract 25 from both sides of the equation.