17. The coordinates of triangle ABC are A (-1, 12), B (1,6), and C (0,9). Triangle DEF is a dilation of triangle ABC with a scale factor of 3/4 What are the coordinates of triangle DEF?​

Sound travels about 750 miles per hour. a) suppose it takes about 1.5 seconds to hear the echo. how far away is the canyon wall, in feet? for this i got 825 ft b) suppose you stand 1,925 feet from the canyon wall and sound the horn. how long will it take to hear the echo? (i'm stuck on this)