SOLUTION: how do I solve the following formula: 4X Squared + 70X = -150 thank you

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Question 71133: how do I solve the following formula:
4X Squared + 70X = -150
thank you


Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
4X^2+70X=-150
4X^2+70X+150=0 the process here is that you have to factor both the 4 & the 150 so that the sum of the products = 70. thus the factors of 4 are 1&4, 2&2. the factors of 150 are 1&150, 2&75, 3&50, 5&30, 6&25, 10&15.
examples of the sum of products are: 2*2+2*75=4+150=154, 1*6+4*25=6+100=106,
2*10+2*15=20+30=50 & 1*10+4*15=10+60=70 which is the pair of factors you want.
hope this explains what needs to be done. it is a trial & error process or you could use the quadratic equation:
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
(4X+10)(X+15)=0
4X+10=0
4X=-10
X=-10/4
X=-2.5 ANSWER
X+15=0
X=-15 ANSWER