$3.20
2.99 • 7% = 0.2093
2.99 + 0.2093 = 3.20
Since he must not exceed 8 hours driving in a day:
Let the distance of the picnic be = x km.
Therefore time for forward journey = x / 60
Return journey = x / 50
The total trip should not exceed 8 hours.
Therefore: x / 60 + x / 50 <= 8. LCM = 300
Taking LCM and multiplying on both sides:
5x + 6x <= 8(300)
11x <= 2400
x <= 2400/11
x <= 218.18
The picnic spot must be less than or equal to 218.18 km.
Point B is located at point (4, -2)
The first one is 810
The second is -120