# Subtraction in Equivalent Expressions

Warmup

Activity #1

` Practice the Distributive Law.` • Use the distributive property to write an expression that is equivalent to the expression.
• If you get stuck, consider drawing boxes to help organize your work.

(1.) (2.) (3.) (4.) (5.) Activity #2

` Compare two Relations.` • Drag the number tiles (top right) in the boxes below to make a true statement.
• After doing so, use the pen o r tool to illustrate how your statement is true.

• Create another true statement different from the one you created above.
• After doing so, use the PEN or TEXT tools to illustrate how your statement is true.

• Create another true statement different from the two you created above.
• After doing so, use the PEN or TEXT tools to illustrate how your statement is true.

• Create another true statement different from the three you created above.
• After doing so, use the PEN or TEXT tools to illustrate how your statement is true.

Activity #3

` Apply the Properties of Operations to Generate Equivalent Expressions.` • Interact with the applet below to solve as many problems as you can.

For example, apply the distributive property to the expression 3 (2 + x) to produce the equivalent expression 6 + 3x.

Challenge #1

Kiran wrote the expression for this number puzzle: “Pick a number, add -2, and multiply by 5.” Lin thinks Kiran made a mistake. How can she convince Kiran he made a mistake?

(1.) Lin thinks Kiran made a mistake. How can she convince Kiran he made a mistake?

(2.) What would be a correct expression for this number puzzle?

Challenge #2

Here is a calendar for April 2017. Let’s choose a date: the 10th. Look at the numbers above, below, and to either side of the 10th: 3, 17, 9, 11.

(1.) Find the average of these four numbers. What do you notice?

(2.) Choose a different date that is in a location where it has a date above, below, and to either side. Average these four numbers. What do you notice?

(3.) Explain why the same thing will happen for any date in a location where it has a date above, below, and to either side.

Challenge #3

Kiran wrote the expression – 10 for this number puzzle: “Pick a number, add -2, and multiply by 5.”

(1.) Lin thinks that Kiran made a mistake. How can she convince Kiran he made a mistake?

(2.) What would be a correct expression for this number puzzle?

Quiz Time