Ineed this in an ordinary number? ?

Solve the system of equations. y= 2x y= x^2 - 15

Which graph has figures that can undergo a similarity transformation to justify that they are similar? (obviously not the third one)

Aclassroom is made up of 11 boys and 14 girls. the teacher has four main classroom responsibilities that she wants to hand out to four different students (one for each of the four students). if the teacher chooses 4 of the students at random, then what is the probability that the four students chosen to complete the responsibilities will be all boys?