105% =$34.02
100% (cost without sales tax) = 34.02/1.05 =$32.40
Y = mx + b
slope(m) = -2/3
(2,-5)...x = 2 and y = -5
now we sub, we r looking for b, the y int
-5 = -2/3(2) + b
-5 = - 4/3 + b
-5 + 4/3 = b
- 15/3 + 4/3 = b
- 11/3 = b
equation is : y = -2/3x - 11/3...but we need it in standard form
Ax + By = C
y = -2/3x - 11/3
2/3x + y = - 11/3....multiply by 3
2x + 3y = -11 <== standard form
65 % is bigger than 16/25
So with this, you can rewrite the equation as: 
Firstly, solve the multiplication: 
Next, combine like terms, and <u>your answer will be:
</u>
(6,-5) (6,-8)
y2-y1/x2-x1
-8+5/6-6
-3/0
Undefined should be the answer. Hope this helped (: