I’ve figured out all of these except for the third and fifth problems. please help !

What value of x will make the triangles similar by the sss similarity theorem?

You are at a restaurant and owe $38 for your meal. you want to leave a 20% tip. how much will your tip be?

The holiday party will cost $160 if 8 people attend.if there are 40 people who attend the party, how much will the holiday party cost