1. (2,3)
2. (-1,-1)
3. infinitely many
4. coincident
5. consistent independent, coincident, inconsistent (in that order)
When stone hits the ground, it's height will be zero, and since we're finding the time that's required for the stone to hit the ground, we can set h = 0 and solve for t.
Since x represents the year, year 15 will be 15 years.
Plug in "15" as your "x"
y = -2(15)^2 + 36(15) + 6
15^2 = 225 (Exponents come before multiplication)
y = -2(225) + 36(15) + 6
y = -450 + 540 + 6
y = 90 + 6
y = 96
<em>The answer is B</em>
1 yd equals 3 feet. 1 yd equals 36 inches.