Equations

Student Name: _____________________________

Date: ________________

Equations: Who Is Correct? Jack, Tabitha, and Jodie each wrote an equation to represent the following situation. Martha has a group of rectangular prisms. Each rectangular prism has a volume of 128 cubic inches and a width of 4 inches. The table shows the relationship between each prism’s length, l, and its height, h. Length, l (inches)

Height, h (inches)

1

32

2

16

4

8

8

4

Write an equation that represents the relationship between the height, h, of a prism in inches and l, the length in inches. Jack’s Equation 128 = l•h 4 Is Jack’s equation correct? Justify your answer.

Tabitha’s Equation

Jodie’s Equation

128 ÷l 4 Is Tabitha’s equation correct? Justify your answer.

4 • 128 = h • l

h=

Is Jodie’s equation correct? Justify your answer.

Communicating about Mathematics What questions would you ask Jodie about her equation? Why?

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