Five friends went to an amusement park. The group wanted to calculate the total cost, so Kathie wrote the expression 5x + 70. Each of her friends wrote expressions, too.
Determine which friends' expressions are equivalent to Kathie's. Show or explain your reasoning.
Kathie: 5x+70
Stephanie: 3(x+30)+2x−20
Jon: 3x+30+2x−20
Mary: 5(x+14)
Nicole: 3(x+30−20)+2x