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

Mat bought a phone for $100. he has to pay $30 per mouth. if he has paid $640 in total, how many mouth has he had the phone?

Which of the following parabolas opens up?

Acompany that makes? hair-care products had 5000 people try a new shampoo. of the 5000 ? people, 35 had a mild allergic reaction. what percent of the people had a mild allergic? reaction?