Luis and david are visiting sara who lives between their homes. to go home, luis rides his bike east for 20 minutes at an average speed of 24 miles per hour. david rides his bike west for 45 minutes at an average speed of 20 miles per hour. how far apart do luis and david live in miles?

Luis and David live 23 miles apart.

Step-by-step explanation:

They ride in opposite direction(west, east), so we add the distances that both traveled, and this is how far apart they live.

Luis

Luis rides at an average speed of 24 miles per hour. He rides for 20 minutes, which is 1/3 of an hour. 24/3 = 8. This means that Luis rode for 8 miles.

David

David rides at an average speed of 20 miles per hour. He rides for 45 minutes, which is 3/4 of an hour. So 3*20/4 = 15 miles. David rides for 15 miles.

8+15 = 23.

So Luis and David live 23 miles apart.

check the picture below.

well, the angle at the vertex d is clearly not a right-angle, let's check for the one at the vertex f which does look like,   however if it's indeed, that means ef is perpendicular to df, in which case their slopes will be negative reciprocal of each other.

so the negative reciprocal of the slope of ef is 1, however the slope of df is not 1, is 1/2, so nope, they're not perpendicular lines.