Model Algebraic Equations

What equation is modeled?

• 3 = 6

• 3x = 6

• x = 6

• 3 = 6x

The difference of 100 and x is 57.

• 100 - 57 = x

• x - 100 = 57

• x + 100 = 57

• 100 - x = 57

The total area decreased by 75 feet is 250 square feet.

• 75 - a = 250; a= 175

• a - 75 = 250; a= 325

• 250 - 75; a=175

• x -250 = 75; a = 175

Solve: Carla's height plus 4 inches is 68.

• Carla is 72 inches.

• Carla is 66 inches.

• Carla is 62 inches.

• Carla is 64 inches.

An electrician charges $25 to make a house call, plus $40 for every hour of work. Which equation shows how to find C, the total cost for having the electrician work for h hours?

• C = 25+40h

• C = 65+h

• C = 65h

• C = 25h +40

Write an equation for
 17 less than H equals 42

• 17-H=42

• H-17=42

• H+17=42

• 17+H=42

Write an equation for
 8 less than y is 6

• y-8=6

• y+8=6

• 8+6=y

• 8-y=6

There are 3 tennis balls in each can.  The coach bought a total of 27 tennis balls.  Write and solve a multiplication equation to find how many cans the coach bought.

• x/3 = 27

• 27x = 3

• x/27 = 3

• 3x = 27

Write the equation for the following situation:
Steve runs 6 miles per hour. When he was finished, he ran a total of 18 miles.

• x/6 = 18

• 6x = 18

• x + 18 = 6

• 18x = 6

To isolate the variable in this equation, what should you do?

2x = 4

• Divide the left side by the value of 2

• Divide both sides by the value of 2

• Divide the right side by the value of 2

• Multiply both sides by the value of 2