What is a proportional relationship? what does a graph look like if there is a proportional relationship?

Satchi found a used bookstore that sells pre-owned dvds and cds. dvds cost $9 each, and cds cost $7 each. satchi can spend no more than $45.

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

Evaluate the expression for the given value of the variable. ∣-4b-8∣+∣-1-b^2 ∣+2b^3 ; b=-2