Equations Quick Check

What equation is modeled?  Solve the equation.

• x -6 = 13     x = 19
• x + 6 = 13    x = 7
• x + 6 = 13    x = 8
• x - 6 = 13   x = 7

Solve for x:
4(1-x) + 3x = -2(x+1)

• x = -6
• x = 6
• x = 3

Solve:
2(4x-3) - 8 = 4 + 2x

• x = 5/3
• x = 3
• x = 1
• x = 2

7n + 2 = 4n + 17

A local bakery has a daily operating cost of $1800 plus a cost of $10 per cake they make. If a cake sells for $15, which equation could be used to determine the minimum number of cakes, c, they must sell each day to earn a profit?

• 15c < 1800 + 10c

• 15c > 1800 + 10c

• 15c = 1800 + 10c

• 10c < 1800 + 15c

At the beginning of the year, Ethan has $800 in his savings account and Faith has $1,280 in her savings account.  Each month, Ethan deposits and additional $25 in his account, while Faith withdraws $15 from her account.  Write an equation to show after how many months will Ethan’s account have a greater balance than Faith’s account?

• 800 - 25x  < 1280 - 15x
• 800 + 25x < 1280 - 15x
• 800 + 25x  > 1280 - 15x
• 800 + 25x >  1280 + 15x

A hockey season ticket holder pays $72.48 for all of her tickets plus $6 for a program each game. A second person pays $18.08 for a ticket to each game, but doesn’t buy programs.  Write an equation that shows when the two fans will pay the same amount.
In how many games will they have paid the same amount? 

• 18.08 + 6x = 72.48x;  6 games
• 72.48 + 6x = 18.08; 9 games
• 72.48 + 6x = 18.08x; 9 games
• 72.48 + 6x = 18.08x; 6 games

Peppy Pets charges a flat fee of $15 plus $3 per hour to keep a dog during the day. Happy Hounds charges a flat fee of $21 plus $1 per hour. For how many hours is the total fee charged by the companies the same?

• 2 hours
• 3 hours
• 4 hours
• 5 hours

Which situation can be represented by the equation 
1500 - 50x = 2000 - 100x

• There are two water tanks in the city.  One tank has 1500 gallons and gains 50 gallons each hour.  The other tank has 2000 gallons and gains 100 gallons each hour.  When will the tanks have the same amount of water?
• There are two water tanks in the city.  One tank has 1500 gallons and loses 50 gallons each hour.  The other tank has 2000 gallons and gains 100 gallons each hour.  When will the tanks have the same amount of water?
• There are two water tanks in the city.  One tank has 1500 gallons and loses 50 gallons each hour.  The other tank has 2000 gallons and loses 100 gallons each hour.  When will the tanks have the same amount of water?
• There are two water tanks in the city.  One tank has 1500 gallons and loses 50 gallons each hour.  The other tank has 2000 gallons and loses 100 gallons each hour.  When will the bigger tank have more water?