1. Adding and Subtracting Equations
Objective:
Learn to solve addition and subtraction equations.

2. How will I use this in real life?
Sam bought a hamburger and a hot-dog for a total of $6. If the cost of the hamburger was $4,  what was the cost of the hot-dog?
Answer:
Hamburger Hot dog = $6
+ = $6
$ ? = $6
But if we use an equation, it would look like this…
4 + H = 6

3. X + 5 -5 = 8 - 5 2. Subtract 5 from each side of the equal sign.
How do we solve adding/subtracting equations? There are 2 possible ways… When solving equations your goal is to find the value of the variable by isolating it. To do this you must do the inverse operation by adding or subtracting to both sides of the equal sign.
Example 1: Steps:
X = Write the equation.
X = Subtract 5 from each side of the
equal sign.
X = Cancel the opposites.
X = Subtract
X = Write the answer.

4. The golden rule when solving equations is: Whatever you do to one side of the equal sign you must do to the other.
Example 2: STEPS:
X = Write the equation.
-2 = look at the operation.
X = Find the inverse operation.
4. Cancel the opposites.
5. Add/Subtract
6. Write the answer.
Examples:
15 = T W = 41
27 = T

5. Homework: H + 3 = 14 6. 7 = C - 5 M + 8 = 22 7. J - 12 = 18 P + 5 = 15
Solve each equation.
H = 14
M = 22
P = 15
17 = Y + 8
B = 6
= C - 5
J = 18
14 = F
25 = R
A = 4.2