Variables
What is a variable?
A Variable is a letter that stands for a value that we do not know yet.
3y = 9
y = 3
y + 16 = 39 + 12
y = 35
13 - 6 x 2
1
Open Circle or Closed Circle: y < 4
Open cirlcle
What is an example of a variable?
Any letter (ex: a , b , c , x , y , z)
y/12 = 6
y = 72
2y + 1 = 13
y = 6
(16 - 4)2+ 2 x 9
162
Solve: 3y > 17 - 2
y > 5
Miss Halaby has 96 cookies for a bake sale. After selling some, there are 29 cookies left. What equation would represent this problem?
96 - y = 29
y - 6 = 39
y = 45
7y + 2 = 33 - 3
y = 4
9 + 5 x 16 -2
87
Solve: 4y + 6 < 14
y < 2
Is the variable always the same value in the same equation?
16 - y = 5
y = 11
y/5 + 6 = 46
y = 8
7 x (13-6) + 112
170
Solve: y/7 > 6
y > 42
Write an equation for the following: If Mr. T makes $19 per hour and makes $3610 per month, how many hours did he work?
190 hours
y/-8= -12
y = 96
2y - 6 + y = 69
y = 25
142 - 16 x 2 + (17 -9)2
228
Solve: -9y - 14 < 12 + 10
y > - 4