I've been working on this question and I just don't know how to arrive at the correct answer!!(adsbygoogle = window.adsbygoogle || []).push({});

Here's my question.

Two identical cars, each travelling at 50km/h, one travelling north and one travelling east, collide at an intersection and become locked together.

What is the speed of the joint wreck immediately after the collision?

I tried using the pythagoras theorum to attempt finding the new speed.

Root(50^2 + 50^2) but this gave me a new speed of 70.7km/h which I believe is wrong since the are moving at a faster speed.

How do I solve this question?

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# Homework Help: A collision question

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