Vocabulary
Variable
A symbol—usually a letter like x , y, or z—used to represent an unknown number, a placeholder, or a quantity that can change.
2x = 10
x = 5
2x + 4 = 28
x = 12
12 + 7x = x
x = -2
What is the y-intercept in the equation: y = 3x -1
-1
A fixed, unchanging value.
x/3 = -9
x = -27
-3x + 5 = 41
x = -12
6x - 10 = x + 10
x = 4
Simplify the following fraction: 6/24
1/4
Coefficient
A numerical or constant factor that is multiplied by a variable in an algebraic expression or equation (e.g., in the term 5x, 5 is the coefficient).
x + -11 = -53
x = -64
x/7 + 2 = -3
x = -35
1 = 14x + 22
x = -1.5
-27 -84 = ?
-111
Reciprocal
A reciprocal is a number you multiply by another number to get exactly 1. To find a reciprocal, simply "flip" the fraction upside down.
-x = -52
x = 52
⅓ x + 5 = -1
x = -18
1.8 + x = 1.8 + 0.25x
x = 0
301 divided by 7 = ?
43
Inverse Operations
Inverse operations are mathematical operations that reverse or "undo" one another.
0.25x = 7
x = 28
0.75x - 6 = -3
x = 4
–3x + 6 = 12x – 15
x = 1.4
6(4x–6) = 4(9–3x)
x = 2