A mathematical phrase that contains numbers, operations, and/or variables (but no = sign). Example: 5x + 4y + 5 - 2x
expression
8a + 15a + a + 9
24a + 9

x = 30
Evaluate: (3x)+7x2 when x=3
72
7(x + 1) =3(x + 5)
x=2
Two angles that add up to 180o
supplementary angles
12c - 6c - (-30)
6c+30
Solve for x: 
x = 61
Evaluate when x=2 and y=1
2(x2 + y)
10
3(x + 5) - 1=5x +2
x=6
Angles that are opposite each other. They share a vertex. The angles are equal.
Vertical Angles
2(x2 + y)
2x2+2y
Solve for x.
x=29
Evaluate when m=3 and n=1
3mn-(2m3 + 2n)
-47
3x+1=4x-6
x=7
Angles that share a vertex and one side.
Adjacent angles
3x2y + 4xy + 4y + 6 + 7x2y
10x2y + 4xy + 4y + 6
Solve for y: 
y=13
Evaluate when x=2 and y=0
(4x+y)/(2x + 3xy)^2
1/2
8x+1=4x+4
x=3/4
Angles that add up to 90o
complementary angles
4( 2x2 + 3x2)
20x2
What is the measure of the given angles? 
124o
Evaluate when x=0 and y=2
4(2x2 + 3y2)
48
4x-5(2x-6)=3(3x+1)
x=9/5