Grade 10 - Algebra

One-step equations:
Note: Notice that addition and subtraction are the opposite operations of each other. x + 9
= x + 9 - 9
= x
When we add and subtract the same number, they cancel out.
In equations, we want to solve for unknowns.
Ex.1: x + 4 = 7 We want x all by itself, so how do we get rid of the +4?
Subtract 4 from both sides
x + 4 - 4 = 7 - 4
x = 3
Ex. 2 y - 8 = 12
y -8 + 8 = 12 + 8
y = 20

Once you do enough of the questions, you'll notice we are just putting the opposite operation on the other side of the equal sign.
Also notice multiplication and division are also opposite operations.
3x = 12
Divide both sides: 3x/3 = 12/3
x = 4
Complete Handout. #1-6,9,11,14,15,17,19