SOLUTION: Please explain how to solve this problem, -0.5m - 0.75 = 2.15 I don’t understand what the constant is and why I have to move it to the right

Algebra ->  Equations -> SOLUTION: Please explain how to solve this problem, -0.5m - 0.75 = 2.15 I don’t understand what the constant is and why I have to move it to the right      Log On


   

Question 1155522: Please explain how to solve this problem, -0.5m - 0.75 = 2.15
I don’t understand what the constant is and why I have to move it to the right
Found 3 solutions by josmiceli, ikleyn, MathTherapy:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
An unknown quantity can be any letter or symbol, so
+m+ is perfectly OK to use.
Don't think in terms of "moving" things to the left or right.
Just about the only rule you need is:
" Whatever you do to one side of an equation, you must do
the same thing to the other side."
----------------------
You want to end up defining what a positive +m+ is,
not a negative +m+ is, so your first step is "Add +.5m+
to both sides."
------------------------
+-.5m+-+.75+=+2.15+
+.5m+=+.5m+
Now add these equations
+0++-+.75+=+.5m+%2B+2.15+
Now subtract +2.15+ from both side
+0++-+.75+=+.5m+%2B+2.15+
+-2.15+=+-2.15+
------------------------
+-2.15+-+.75+=+.5m+
Sum the terms on the left side
+-2.9+=+.5m+
Divide both sides by +.5+
+-5.8+=+m+ answer
----------------------------------
Now you can check the answer:
+-.5m+-+.75+=+2.15+
+-.5%2A%28+-5.8+%29+-+.75+=+2.15+
+2.9+-+.75+=+2.15+
+2.15+=+2.15+
OK
Hope this helps






Answer by ikleyn(52777) About Me  (Show Source):
You can put this solution on YOUR website!
.

In this site, there is the lesson
    - HOW TO solve a linear equation
written for those beginners, who make their first steps in learning this subject: solving simple linear algebraic equations.

Consider this lesson as your textbook, handbook, tutorials and (free of charge) home teacher.

Hope it will help you to sail and to survive in the sea of algebraic equations.

Happy learning (!)

Every time, when you have difficulties with your Algebra problems, come to this forum for help.



Answer by MathTherapy(10551) About Me  (Show Source):
You can put this solution on YOUR website!

Please explain how to solve this problem, -0.5m - 0.75 = 2.15
I don’t understand what the constant is and why I have to move it to the right
- 0.5m - 0.75 = 2.15

We need the variable "m," on 1 side and the CONSTANT on the other, since the value of the variable, "m" is being sought.

To leave the variable on the left side, we NEED to get rid of the - 0.75, so we ADD .75 to BOTH sides so on the left side, - 0.75 will be zeroed out, as follows:

- 0.5m - 0.75 =  2.15

       + 0.75  + 0.75

- 0.5m        =  2.9