Answer number 18 and 19

What are the values of a, b, and c in the quadratic equation 0 = x2 – 3x - 2? a = 1, b = 3, c = 2 a=, b = -3,c=-2 a = 1, b = 3, c= 2 a = 1.0= -3, c = 2

To solve the system of equations below, pedro isolated the variable y in the first equation and then substituted it into the second equation. what was the resulting equation? { 5y=10x {x^2+y^2=36

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?