Equations and Inequalities 2.1 Retest Review

Which expressions show the cost for each company, where x is the number of items?

• A: 21x + 2 B: 7x + 3

• A: 21 + 2x B: 7 + 3x

• A: (21 + 2)x B:10x

• A: 21 + 2 + x B: 7 + 3 + x

Solve the equation below. Type in just the number for the answer.

3x + 20 = 2x + 5

Solve. 8x – 4 = 4(x + 6)

Type in just the number for the answer.

Company A rents copy machines for $0.04 per copy plus $200 fee. Company B charges $0.02 per copy plus a $800 fee. For what number of copies do the two companies charge the same amount? Write and solve an equation. Then type just the number of the solution.

At the store each book has a cost of x dollars. Which situation can be modeled by the inequality?
 $7x>2x-1$  

• The cost of 7 books is greater than the cost of 2 books plus a dollar pencil. 

• The cost of 7 books is greater than the cost of 2 books with a dollar coupon.

• The cost of 7 books is less than the cost of 2 books with a dollar coupon.

• The cost of 7 books is less than the cost of 2 books with a dollar pencil.

Write an equation from the model and solve for x. Type just the number for your answer.

Two 8th grade classes are selling raffle tickets to raise money.

One class is selling ticket for $5 and has already raised $300.

The other class is selling tickets for $3.50 and has already raised $425.

Which equation can be used to find x the number of tickets each class needs to sell so they will raise the same amount of money.

• 5x+300=3.50x+425

• 5+200x=3.50+425x

• 3.50x+5x=300+425

• not here

Solve the equation:
3(x - 1) = 2x + 9

• x = 12
• no solution
• x = 10
• x = 6

Write an inequality to represent the following relationship:
Three times a number minus two is less than the number plus ten.

• 3x - 2 < x + 10
• 2 - 3x < x + 10
• 3x - 2 > x + 10
• 2 - 3x > x + 10

Select the situation that could be modeled by: 12 + 5x = 18+3x

• Derek charges a base fee of $12 to walk a dog plus $5 per hour. Darla charges a base fee of $18 plus $3 an hour to walk a dog. After how many hours would they make the same amount of money?
• Andy buys 12 sodas for $5 each. Alex buys 18 sodas for $3 each. If they each spent the same amount, how much did they spend?
• Brian charges $12 for a hat and $5 per shirt. Blake buys 3 hats and 18 shirts. How many hats and shirts must they sell to make the same amount of money?