1. solve the problem. a cross-country skier reaches the 12-km mark of a race 40 min after reaching the 5-km mark. find the speed of the skier.
a) 7 km/hour b) 21/2 km/hour c)28 km/hour d)18 km/hour
2. determine the equation of the line described. put the answer in the slope-intercept form, if possible. through (9,2), perpendicular to x=-8
a) y=2 b) y=-8 c) y=-2 d) x=-8
3. solve. on a recent trip, sarah's car traveled 20 mph faster on the first 130 miles than it did on the remaining 80 miles. the total time for the trip was 4 hr. find the speed of sarah's car on the first part of the trip.
a) 39 mph b) 42 mph c) 62 mph d) 10 mph
4. write a slope-intercept equation for a line with the given characteristics. passes through (4,7) and (0,-8)
a) y=3/8x-8 b) y=15/4x-8 c) y=-3/8x-8 d) y=-15/4x-8