Two rays that intersect at their initial point.

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?

Anumber cube is rolled two times in a row. find the probability it will land on 2 on the first roll and a number greater then 4 on the second roll

Write the equation in general quadratic form: plz !