Which expression is equivalent to (x+3)+y? A: x+(3+y)
B: x(3+y)
C: (x+3)+(x+y)
D: (x+3)+(3+y)

Mrs. morton has a special reward system for her class. when all her students behave well, she rewards them by putting 3 marbles into a marble jar. when the jar has 100 or more marbles, the students have a party. right now, the the jar has 24 marbles. how could mrs. morton reward the class in order for the students to have a party?

The figure below shows rectangle abcd and the triangle eca on a coordinate plane. which of the following expressions represents the perimeter of triangle of triangle eca in units

Need showing work for this problem 56.25 ×25.80