For 35:
If the price starts at $25,000 and decreases by 15% each year, that means it is 85% of the value it was the previous year (100% - 15% = 85%). We write this out as an exponential function using the equation P(t)=p(r)^t where P(t) is the price function during time t, p is the original price, and r is the 85% we found. Plugging this in we get P(7)=25000(0.85)^7 which is about $8014, rounded to $8000. Therefore A is correct.
For 36:
We want to isolate y to have it by itself. First subtract 12x on both sides, then divide by 3 on both sides. We are left with y=2-4x. The slope is -4 and the y-intercept is 2, found by looking at the equation.