Name: Maria Rainsdon
Who is asking: Student
Level: Middle
Question:
I don't understand how to solve these multiple step problems. I wasn't there when my teacher explained it and I am really lost. Here is one of the probs I don't understand: 3m+6=m6. Could you please reply asap? Thanks
Hi Maria,
You have the equation
3m + 6 = m  6
and you want to "solve for m". That is you want an equation that is equivalent to
3m + 6 = m  6
but which has the form
m = "a number"
I am going to call this equation the target equation.
One feature I see in the target equation that is not true of your original equation is that the letter m only appears on the left of the equal sign. To "remove" m from the right side of the original equation I add m to both sides to get
3m + 6 + m = m  6 + m
On the left side 3m + m = 4m and on the right side m + m = 0 and thus this equation simplifies to
4m + 6 =  6
This equation is equivalent to the original equation since I obtained it from the original equation by adding the same amount (m) to both sides.
I now want to "remove" the 6 from the left side of the equation and I do this by adding 6 to both sides of the equation to get
4m + 6  6 =  6  6
which simplifies to
4m =  12
All that remains now is to "remove" the 4 from the left side while maintaining the equality of the two sides. This I do by dividing both sides by 4 to get
4m/4 =  12/4
or
m = 3
I hope this helps,
Penny
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