Prove, using the second derivative, that the general quadratic y= ax^2+bx+c, is:
a) always convex when a>0
b) always concave when a <0

Asystem of linear equations contains two equations with the same slope. select all of the correct statements. i a. the system may have two solutions. - b. the system may have infinitely many solutions. c. the system may have one solution. o d. the system may have no solution. submit