What property is illustrated by the equation 6 + 7 = 7 + 6

A large cheese pizza costs $18. Each topping you add on costs $1.50. How much would it cost to get a large cheese pizza with c toppings added? Write your answer as an expression.

What property is illustrated by the equation 6(x + y) = 6x + 6y

Sarah received $55, for her birthday. She used some of that money to buy 3 shirts priced at m dollars each. How much money does Sarah have left? Write your answer as an expression.

What property is illustrated by the equation (6 + 7) + 8 = 6 + (7 + 8)

(2x + 5) - (6x + 3)

Simplify 5a - 6b + 4a + 3b

7(a + 8) - 5a + 4

(2x + 4) + (3x + 5)

3 - 5(a - 4)

A cell phone company charges $40 per month(m) plus a $35 activation fee. How much would the service cost for the first 2 months(m)?

Marco's mom gave him d dollars for his allowance one week. He also earned $14.55 for his newspaper route that week. Write your answer as an expression.

3(a - 14) - 5(a + 12)