Algebraic expression:

1
Algebraic expression - a collection of
numbers, variables, operations, and grouping
symbols Examples 3x 4x 6
7x 3

Algebraic expressions in situations Area of a
rectangle A lw A area l
length w width Interest earned
I Prt I interest P principal r
interest rate t time (years)
Distance D rt D
distance r rate t time

2
Evaluate the algebraic expression.

• 2x 1, when x 4
• 2(4) 1 (substitute 4 for x)
• 8 1
• 9

• 2r s 4, when r 4 and s 5
• 2(4) 5 4 (substitute)
• 8 5 4
• 7

• (a 2) 4a, when a 4
• (4 2) 4(4) (substitute 4 for a)
• 2 16
• 18

• 3x(4 x), when x 2
• 3(2)(4 2) (substitute 2 for x)
• 6(6)
• 36

3
Evaluate the algebraic expression.

• x (3y 4), when x 6 and y 2
• 6 3(2) 4 (substitute)
• 6 6 4
• 6 2
• 3

• xyz - 2xy 3yz
• when x 1, y 2, z 3
• 1(2)(3) - 2(1)(2) 3(2)(3)
• 6 - 4 18
• 20

8.
7.
4

• A football field is 110 meters long and 49 meters
  wide. How many
• square meters of artificial turf are needed to
  cover the field?

Area of a rectangle A lw A 110(49) A 5390
m2
5

• A car traveled for 2 hours at a constant speed of
  58 miles per
• hour. How far did the car travel?

Distance D rt D 58(2) D 116 miles