SOLUTION: X^2 + MX + 12 = 0 the first root of x is 3 times larger than the second root x what are the values of M

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Question 925474: X^2 + MX + 12 = 0
the first root of x is 3 times larger than the second root x what are the values of M
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Choose the case level and stay with the choice.
I am using all lower-case.

Roots x=%28-m%2B-+sqrt%28m%5E2-4%2A12%29%29%2F2

m%5E2-48%3E=0
m%5E2%3E=48
m%5E2%3E=2%2A2%2A2%2A2%2A3
m%3E=4sqrt%283%29 OR m%3C=0-4sqrt%283%29


%28-m-sqrt%28m%5E2-48%29%29%2F2=3%28-m%2Bsqrt%28m%5E2-48%29%29%2F2
-m-sqrt%28m%5E2-48%29=-3m%2B3sqrt%28m%5E2-48%29
2m-sqrt%28m%5E2-48%29=3sqrt%28m%5E2-48%29
2m=4sqrt%28m%5E2-48%29
m=2sqrt%28m%5E2-48%29
m%5E2=4%28m%5E2-48%29
m%5E2=4m%5E2-4%2A48
0=3m%5E2-4%2A48
3m%5E2=4%2A24%2A2
m%5E2=4%2A8%2A2
highlight%28m=-8%29 or highlight%28m=8%29