Algebra Rules!
What is a variable?
The variable is a symbol for a number we don't know yet. It is usually a letter.
Solve
b + 3 = 12
2g + 4 = 14
g = 5
Daniya has 10 books in her library. She bought several books at a yard sale over the weekend. She now has 51 books in her library. How many books did she buy at the yard sale ?
10 + b = 51
6 = 2(y + 2)
y = 1
What is the main goal when solving and algebraic equation?
To get the variable by itself.
x = 7
6p - 5 = 61
p = 11
Last week Azlan had 46 dollars. He washed cars over the weekend and now has 96 dollars. How much money did he make washing cars ?
46 + c = 96
Joshua bought a soft drink for three dollars and five candy bars. He spent a total of eighteen dollars. How much did each candy bar cost ?
Equation + solve
5y + 3 = 18
y = 3
What happens to an operation when it crosses the equal sign?
It becomes the opposite.
f/7 = 42
f = 294
m / 5 + 9 = 11
m = 10
Jordan bought six new baseball trading cards to add to his collection. The next day his dog ate half of his collection. There are now only forty - six cards left. How many cards did Jordan start with ?
h + 6 / 2 = 46 OR h / 2 + 6 = 46
2(x-6) -1 = 15
x = 14
What is the systemaic trial method?
Substituting numbers for the variable, and using the answers to help guide your next choice
b = 582
15b - 5 = 535
b = 36
Oceanside Bike Rental Shop charges 14 dollars plus 9 dollars an hour for renting a bike. Hellen paid 95 dollars to rent a bike. How many hours did she pay to have the bike checked out ?
9x + 14 = 95
Heyam had two hundred forty - five dollars to spend on six books. After buying them she had seventeen dollars. How much did each book cost ?
Equation + solve
6x + 17 = 245
x = 38
What is the inspection method?
Using the numbers in an algebraic equation to help solve
There are forty seven popular trees currently in the park. Park workers will plant more popular trees today. When the workers are finished there will be ninety two popular trees in the park. How many popular trees did the workers plant today ?
47 + t = 92
t = 45
n - 31 / 4 = 2
n = 39
Last summer, 333 students went on a trip to the zoo. All 8 buses were filled and 5 students had to travel in cars. How many students were in each bus ?
8n + 5 = 333
42 + 5t = 8t
t = 14