Addition and Subtraction Equations

Friday and today, Monday, we worked on addition and subtraction equations.  Here are two examples:

y + 24 = 30

There are three steps, first copy down the problem.  Done.  Next do the inverse operation of the problem on the side with the variable (letter)

y + 24 = 30
   - 24 = -24

You'll notice that the + 24 and the - 24 will cancel out, or equal zero, leaving us with just y on that side, so we now have:

y = 30 - 24, which is y = 6. 

The same is done with subtraction, but the inverse operation will now by addition.  Example:

101 = b - 48

Inverse operation would be to isolate the variable (letter) so it is by itself, so apply + 48 to both sides:

101 = b -48
+48 = b + 48

On the right we are left with just b, since - 48 and + 48 = zero

101 + 48 = b, solve for b.  101 + 48 is 149, thus 149 = b, or b = 149, either way. 

The test is on Thursday and we are going to continue the same types of problems with multiplication and division, doing the inverse operations of each to solve for the variable (letter). 

Enjoy and check back this weekend for an open ended family problem solving opportunity.  More details to come. 

Mr. Flaten