2 km
Change 54 minutes to hours: \(\frac{54}{60} = \frac{9}{10}\) hours
Let t = time it takes to get to his friend's house
Thus \(\frac{9}{10} -t\) = time it takes to return home
Distance to Friend's house = Distance back home
\(4t=5( \frac{9}{10} -t)\) distance = speed x time
\(4t= \frac{9}{2} -5t\) distributive property
\(9t= \frac{9}{2}\) add 5t to both sides of the equation
\(t= \frac{1}{2}\) divide both sides by 9
To find the distance to the friend's house 4 x 1/2 = 2 km
