Find the value of x in each case: Please help me

It's an easy 40 points if you answer this

The triangles are similar. what is the value of x? x=

In a class, there are 12 girls. if the ratio of boys to girls is 5: 4 how many boys are there in the class

Sam is a waiter at a local restaurant where he earns wages of $5 per hour sam figures that he also eams about $3 in tips for each person he serves sam works 6 hours on a particular day. if n represents the number of people sam serves that day, which of the following functions could sam use to figure ehis total earings for the do o a. en) = 30 o b. en) = 5n+ 18