SOLUTION: Please help, continued.. m^2-25=0

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Question 265123: Please help, continued..
m^2-25=0
Answer by JBarnum(2146) About Me  (Show Source):
You can put this solution on YOUR website!
this one if you can recognize the factors off the bat it will save you from havving to do the quadratic formula. since B=0 in Ax%5E2%2BBx%2BC=0 your looking for 2 of the opposite numbers when multiplied together you get -25. so %28z%28-z%29%29=-25
-z%5E2=-25%29
z%5E2=25
sqrt%28z%5E2%29=sqrt%2825%29%29
z=5%29
with every quadratic equation theres 2 answers, from above you know "z" is both negative and positive, so
%28m%2B%28z%29%29%28m%2B%28-z%29%29
%28m%2B5%29%28m-5%29
m=-5,5
If you dont understand how to do this short version above then just go on to the quadratic equation solver:
Ax%5E2%2BBx%2BC=0
m%5E2-25=0 A=1 B=0 C=-25
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation am%5E2%2Bbm%2Bc=0 (in our case 1m%5E2%2B0m%2B-25+=+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=%280%29%5E2-4%2A1%2A-25=100.

Discriminant d=100 is greater than zero. That means that there are two solutions: +x%5B12%5D+=+%28-0%2B-sqrt%28+100+%29%29%2F2%5Ca.

m%5B1%5D+=+%28-%280%29%2Bsqrt%28+100+%29%29%2F2%5C1+=+5
m%5B2%5D+=+%28-%280%29-sqrt%28+100+%29%29%2F2%5C1+=+-5

Quadratic expression 1m%5E2%2B0m%2B-25 can be factored:
1m%5E2%2B0m%2B-25+=+1%28m-5%29%2A%28m--5%29
Again, the answer is: 5, -5. Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B0%2Ax%2B-25+%29