<u><em>Answer:</em></u>
14 miles
<u><em>Explanation:</em></u>
<u>The relation that will be used to solve this problem is:</u>

<u>which can be rewritten as:</u>

<u>Assume that:</u>
Distance from your house to your friend's house is d
Time taken from your house to your friend's house is t₁
Time taken from your friends house to your house is t₂
<u>1- From your house to your friend's house:</u>
Average rate = 35 miles/hour
<u>Therefore:</u>

<u>2- From your friend's house to your house:</u>
Average rate = 40 miles per hour
<u>Therefore:</u>

<u>3- Round trip:</u>
We know that the round trip took 45 minutes which is equivalent to 0.75 hours
<u>This means that:</u>
t₁ + t₂ = 0.75 hours

Hope this helps :)