Maths Thoughts

Friday, March 5, 2010

For Worksheet 32: To Solve Equations With Two Variables on Both Sides

Hi,

To solve equations like 2a + 5 = 3a - 6, it shouldn't be too tough.

Your mission is to solve for the unknown a in the case of the above equation.

To solve for the unknown , a, you have to move all the unknown terms (2a and 3a) to one side and all constant terms (5 and -6) to the other side.

I will move the smaller unknown term, 2a to the R.H.S of the equation. In order to do that, I will subtract L.H.S by 2a (-2a). To make the equation balance, I need to subtract R.H.S by 2a too.

2a + 5 - 2a = 3a - 6 - 2a

So on the L.H.S, '2a' will be gone as (2a - 2a = 0) and on R.H.S 3a - 2a = a.

5 = a - 6

Now, you will move the constant terms to the L.H.S. You will add 6 to the R.H.S. To balance the equation, you will need to add 6 to the L.H.S.

5 + 6 = a - 6 + 6

11 = a

by D&T Thoughts at 7:28 AM |