CC Algebra I
Name: ______________________________
Lesson 4-Solving 2 Step Equations
Date: ____________
Number_____
Do Now: Solve for x.
1) n + 6 = 11
2) x - 4 = 23
3) 4n = 12
4)
m
= 10
5
An equation is a mathematical statement that states that two expressions and/or
numbers are ________. To solve an equation the goal is to get the ____________
alone on one side of the equal sign. This is done by using ____________________.
Remember inverse operations “undo” each other.
Solve Algebraically
3n + 1 = 7
Use inverse
operations
Solve
n  3  9 Then, check the solution.
4
Solve Algebraically
n  3  9
4
Use inverse
operations
 Add or Subtract
 Multiply or Divide
SOLVE
1)
3)
2)
n  1 6
-2
3n - 1 = 14
2n + 3 = -5
4)
1
y  4  1
2
5)
5n + 7 = -8
7)
6)
8)
**10)
9)
Easy:
-1 – 3w = -7
11) 3n + 6 = 18
Challenging:
12) 4n - 2 = 10
15) -2n + 8 = -4
More difficult:
13)
n
 1  3
7
14)
n
 3  1
2
Work
16)
n
 5  -3
8
17)
n
 1  0
-3
18) -3n - 1 = -10
‘
Steps to solving two-step word problems:
1. Read the problem carefully. Underline any key information.
2. Write a let statement.
3. Write an equation.
4. Solve the equation.
5. Check your answer
Example 1:
Nick opens a savings account with $50. Each week after, he deposits $15. In how
many weeks will he have saved $500?
Step 1: Underline any key information
Step 2: Write a let statement. What does our variable represent?
Step 3: Write an equation:
Step 4: Solve the equation:
Step 5: Re-read the question. Does your answer make sense?
Example 2:
Alex rents a car for one day. The charge is $18 plus $0.12 per mile. Alex wants to
spend exactly $30. How many miles can he drive?
Step 1: Underline any key information
Step 2: Write a let statement. What does our variable represent?
Step 3: Write an equation:
Step 4: Solve the equation:
Step 5: Re-read the question. Does your answer make sense?
Example 3:
Katie wants to buy a bicycle that costs $129. This is $24 more than 3 times what
she saved last month. How much did she save last month?
Solve the following problems and show all your work.
(Remember to use the 5 steps for solving two-step equation word problems!)
19. Ben rents a car for one day. The charge is $20 plus the $0.12 per mile. He wants to spend
exactly $80. How many miles can he drive?
20. When 12 is subtracted from 3 times a number, the result is 24. Find the number.
21. Jill made 20 muffins. She put them into 3 boxes and has two muffins left. How many are in
each box if they all contain the same amount of muffins?
22. If you multiply a number by 3 and then subtract 5, you will get 40. What is the number?
23. Joe went to the hobby shop and bought 2 model sports cars at $8.95 each and some paints. If
he spent a total of $23.65, what was the cost of the paints?
24. Ryan made a $3000 down payment on a car. The total cost of the car was $7500. He made 36
equal monthly payments to pay the car in full. How much did Ryan pay per month?
25. Kendra is buying bottled water for a class trip. She has 16 bottles left over from the last trip.
She buys bottles by the case to get a good price. Each case holds 24 bottles. How many cases will
she have to buy if she wants to have a total of 160 bottles of water?