How do you solve sss similarity theorem and aa similarity theorem

Carl wants to buy a television that cost $500 including taxes. to pay for television he will use a payment plan that requires him to make a down payment of $125 and then pay $70.50 each month for six months what is the percent increase from the original cast of the television to the cost of the television using a payment plan.

When you answer this can you explain

Triangle knm is what is true about the sides of knm