SOLUTION: -10x^2+11x+24=20

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Question 1695: -10x^2+11x+24=20
Answer by smartdude17(30) About Me  (Show Source):
You can put this solution on YOUR website!
In order to solve this, you have to start with the first step. I'll show you:
-10x^2+11x+24= 20 G
-10x^2+11x+44= 0 I,S
x=%28-b%2B-sqrt%28b%5E2-4%2Aa%2Ac%29%29%2F%282%2Aa%29 QF
x=%28-11%2B-sqrt%28121%2B1760%29%29%2F%28-20%29 Sub,S
x=%28-11%2B-sqrt%281881%29%29%2F%28-20%29 S
Now do some thinking. Is 1881 a perfect? If it isn't, you do this:
x=%28-11%2B-43+32%2F87%29%29%2F%28-20%29 S
x=%28-53+32%2F87%29%29%2F%28-20%29 S, (answer #1)
x=32+32%2F87%29%29%2F%28-20%29 S, (answer #2)
In the two answers, M.A.D. them. It means to multiply, add, and divide. Or you could do it this way which leaves it at a radical:
x=-11%2B-sqrt%281881%29%29%2F%28-20%29
Now think! What times what is 1881? Well 9*209=1881, so 9 is a perfect leaving 209 in the sqrt.
x=-11%2B-9sqrt%28209%29%29%2F%28-20%29
And that is your radical answer.