3(y + x) ; use x = 4, y = -1
9
4x + 2x + 7x
13x
What is 22?
4
What do we call a number by itself (with no variable)?
A constant
How do we decide whether to add or subtract first?
Left to right, whichever comes first
4 + xy ; use x = 7 and y = 3
25
5y + 7x + 3 + 4x + 2
5y + 11x + 5
What is 33?
27
A letter of the alphabet that represents an unknown number is called what?
variable
In the expression 9 x 3 - (7 + 9), which step should we start with according to PEMDAS?
7+ 9 in Parentheses
8(5 - x) - y ; use x = 3 and y = 12
4
10x + 4y + 3 + 2x – 2y
12x + 2y + 3
x4 ; use x = 3
How many terms are in this expression?
2x + 5 + 8y
3
Which step should we do first 3 + 42 - 6
Exponent 42
(c + d) + 4c ; use c = 8, d = 9
49
5x + 3y - 4x + 4y + 3
x + 7y + 3
x(y2) ; use x = 3, y = 5
75
What is it called when we add terms that are alike?
Combining Like terms
(5-3)3 - 7
5(f - h) + 2h ; use h = –1, f = 2
13
3a + 2 + 9a - 4a + 5a - 16
9a - 14
y(y 3) + x ; use x = 3, y = 2
19
a number in front of a variable is called what?
coefficient