Yi = B₁ + B₂x2i + B3X3i + ei What properties must a variable z; have to be considered a valid instrument for x3; in the above equation?

1. Simplify: 6 – 8i i) 4+ 3i g) (3 – 2i)? h) 5 – 2i

4. Simplify. Write each expression in the form a + bi: a. (5 – 21) + (-3 +7i) b. (5 – 2i) – (-3 + 7i) 5 -21 c. (5 – 2i)(-3+7i) с. 2751 -31-567 7 351-149

Suppose m and n vary inversely and n = 17 when m = -4. k Inverse variation Formula: y X a) Write an equation that models the variation. b) Find n when m = -136.