SOLUTION: 2m^2-m-15=0 quadratic problem, can you help me solve this step by step with text along side? Im having so many problems solving these types of problems, thanks and God Bless

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Question 638159: 2m^2-m-15=0 quadratic problem, can you help me solve this step by step with text along side? Im having so many problems solving these types of problems, thanks and God Bless
Found 2 solutions by reviewermath, MathTherapy:
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation am%5E2%2Bbm%2Bc=0 (in our case 2m%5E2%2B-1m%2B-15+=+0) has the following solutons:

m%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%28-1%29%5E2-4%2A2%2A-15=121.

Discriminant d=121 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28--1%2B-sqrt%28+121+%29%29%2F2%5Ca.

m%5B1%5D+=+%28-%28-1%29%2Bsqrt%28+121+%29%29%2F2%5C2+=+3
m%5B2%5D+=+%28-%28-1%29-sqrt%28+121+%29%29%2F2%5C2+=+-2.5

Quadratic expression 2m%5E2%2B-1m%2B-15 can be factored:
2m%5E2%2B-1m%2B-15+=+2%28m-3%29%2A%28m--2.5%29
Again, the answer is: 3, -2.5. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+2%2Ax%5E2%2B-1%2Ax%2B-15+%29

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

2m^2-m-15=0 quadratic problem, can you help me solve this step by step with text along side? Im having so many problems solving these types of problems, thanks and God Bless

2m%5E2+-+m+-+15+=+0

We're looking for factors of - 30 (c * a) whose sum is - 1 (b). These are: - 6 & 5, so replacement for b is: (- 6m + 5m)

2m%5E2+-+m+-+15+=+0 now becomes:

2m%5E2+-+6m+%2B+5m+-+15+=+0

2m(m - 3) + 5(m - 3) = 0

(2m + 5)(m - 3) = 0

2m + 5 = 0 or m - 3 = 0

2m = - 5 or m = 0 + 3

highlight_green%28m+=+-+5%2F2%29, or highlight_green%28m+=+3%29

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