Please help with this trigonometry word problem

Question

7. Two cars need to merge into a lane at the vertex of angle C. The angle between lane AC and lane BC

is 45° Car A is 100 feet from the vertex at angle C and Car B is 50 feet from the vertex at angle C. What is the horizontal distance between Car A and Car B?

Answer 1

Draw a figure!

This is a straight application of the rule of cosines:

d² = 10000 + 2500 -10000 cos 45°

If you do not know about the law of cosines, you should either look it up or set up a tutoring session to show it to you.

All you need to do to get the answer from what I have told you is arithmetic.