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-1/6 - 5/4M = -3/5 (solving an equation with fractions)?

i only know how to solve it by converting it to decimals! can someone explain how to do it with fractions? thanks!

Answers (4)

carlosklinead07 profile image
aa12310595 profile image

-1/6 - 5/4M = -3/5


OR -5/4M=-13/30


04fb7ca7f1b2 profile image

Okay, this problem can be easy if you make it easy for you. This is how I would solve it. I would find common denominators for ALL of the numbers, including the -5/4m. (Try using 36 as the denominator.) Then the problem would look like this: -6/36-45/36m= -21/36. (Remember, you have to multiply the top AND the bottom of ALL numbers, keeping the negative sign.) After that, I would solve it like a normal problem by adding. It would look like this:

-6/36-45/36m= -21/36

+6/36 + 6/36

Then, crossout 6/36 to make it less confusing. Add and keep the negative. So the problem would then be:

-45/36= -15/36

After that, solve the problem different ways, because I kind of lost myself with the -15/36 and the -45/36. That's as far as I can get you! Good luck and I hope I've helped!

zwhn5kjoaa profile image

another way to do it (although someone already posted the answer) is to just try to find a common denominator for everything. Remember that if you do something to the top of the fraction, you need to do it to the bottom. (so in their answer, you have -1/6*5/5 + 3/5*6/6, so you would have -5/30 + 18/30.)

Or, you could give everything a common denominator, but that's more complicated...

-1/6*20/20 - 5/4*30/30 * M = -3/5*24/24

-20/120 - 150/120 * M = -72/120

Then you can drop the denominators for everything.

-20 - 150 * M = -72

-20 + 72 = 150 * M

52 = 150 * M

52/150 = M

You get the same answer, but it was a little more work.

It just shows there is more than one way to do a problem.

Reference: 3 years tutoring math, plus many years of doing math