1. Equations as Relations y = 2x is an equation with 2 variables When you substitute an ordered pair into an equation with 2 variables then the ordered pair is a solution of the equation. Independent Variable – the x value of an equation. Dependent Variable – the y value of an equation. The value of y is dependent on the value of x.

2. Examples: 1)Solve y = - x if the domain is { – 3,0,2,6,8}. 2)Solve y = -2x + 1 if the domain is { – 4,-2,0,2, 4}.

3. 3)Solve 2x - 3y = 12 if the domain is {-9, -6, -3, 0, 3, 6, 9}

4. 4) Suppose a rectangle has a perimeter of 42mm. A)Solve the perimeter formula for w. B)State the independent & dependent variables. C)Choose 5 values for l and find the corresponding values of w.