SAT Math: Equation of a Line 3

1. The graph of a line in the xy-plane has a slope of $-\dfrac{5}{2}$ and passes through $(3,-6)$ . The graph of a second line passes through points $(-3,11)$ and $(5,-11)$ . If the two lines intersect at points $(a,b)$ , what is the value of $a-b$ ?

$10$

$12$

$16$

$28$

2. A saleswoman writes an equation to predict annual salary: $y=300x+40000$ (With $y$ representing her total salary, and $x$ representing the number of machines she sells). How many machines does she need to sell to earn $\$ 100000$ .

$60000$

$12000$

$450$

$200$

3. Jackson is on a diet. He currently weighs 250 pounds. His goal is to lose 4 pounds each month. How many months will it take for Jackson to reach his goal weight of 170 pounds?

$10$

$13$