Vocabulary
This is a letter or symbol that represents an unknown number that can change in an algebraic expression.
Variable
5r - 6 + r - 9
6r - 15
A movie theater sells tickets for x dollars each and charges a snack fee of 5 dollars. Later, they add another fee of x dollars and remove a 2 dollar coupon.
Write and simplify an expression for the total cost.
Expression: x + 5 + x - 2
Simplified: 2x + 3
(12x + 15) + (9x - 8)
21x + 7
What are the vocabulary words for this lesson?
Tectonic plates
Plate boundary
Plate tectnics
Convection current
This is a term in an expression that has no variable attached to it.
Constant
-6(4 - 4m) + 2
-22 + 24m
A student buys y notebooks and then buys 2 more notebooks. Each notebook costs 3 dollars, and they use a 4 dollar coupon.
Write and simplify an expression for the total cost.
Expression: 3y + 2(3) - 4
Simplified: 3y + 2
(40m - 22) + (16m + 31)
56m + 9
Matching fossils found on different continents suggest that these landmasses were once...
Joined together/connected.
This is the number that multiplies the variable in a term like 7x or −3y.
Coefficient
3.7x + 6.1(x + 8.1)
9.8x + 49.41
A gym charges m dollars per month and a one time fee of 6 dollars. In the second month, they add another m dollar charge and give a 1 dollar discount.
Write and simplify an expression for the total cost.
Expression: m + 6 + m - 1
Simplified: 2m + 5
2(3.5x + 4) + (6.2x - 7)
13.2x - 3
This process forms new ocean floor when magma rises, cools, and hardens along a long crack in Earth’s crust.
Sea-floor spreading
These are parts of an algebraic expression that are separated by addition or subtraction signs.
Terms
-9(-2x + 10) + 8(x - 9)
26x - 162
The temperature rises by 15t degrees in the morning and by 20 more degrees in the afternoon. Then it drops by 6 degrees at night.
Write and simplify an expression for the total change in temperature.
Expression: 15t + 20 - 6
Simplified: 15t + 14
(9.6 - 2b) + 4(3.5b - 1)
12b + 5.6
What is the name of the supercontinent that scientists believe once existed?
Pangaea
This describes an expression that has no like terms and no parentheses.
Simplest form
3.7(1 - 7.8r) + -3.9(2r + 1.38)
-1.682 - 36.66r
A student reads 6r pages on Monday and 4r pages on Tuesday. On Wednesday, the student reads 18 more pages but forgets to record 5 pages.
Write and simplify an expression for the total number of pages recorded.
Expression: 6r + 4r + 18 - 5
Simplified: 10r + 13
5(1.4m + 6) + (2.6m - 7)
9.6m + 23
What is the name of the bone in our hip region, and what two genetic changes allow us to walk upright?
ilium; it shifted 90 degrees and took more time to harden into bone.