I need help on this one too

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

Is trapezoid abdc the result of a dilation of trapezoid mnpq by a scale factor of ? why or why not? yes, because ab and cd are each the lengths mn and qp. yes, because sides ab and cd are parallel to sides mn and qp. no, because ab is the length mn but cd is the length qp. no, because sides ab and cd have different slopes from sides mn and qp.

Nine more than four times a number is the same as one less than twice the number. find the number?