a = 3
b = -7
c = 4
Explanation
what you need to know:
[tex]a {x}^{2} + bx + c = 0[/tex]
what you have:
[tex]4 + 3 {x}^{2} - 7x = 0[/tex]
so you just rearrange them from highest exponent being on the left to lowest exponent being on the right:
[tex]3 {x}^{2} - 7x + 4 = 0[/tex]
