Which graph represents a function?

Can someone me with this problem i don't understand i need

Which equation shows the quadratic formula used correctly to solve 5x2 + 3x -4 0 for x? cos -3+ v (3) 2-4() 2(5) 3+ |(3)² +4() 205) 3+ (3) 2-4() -3+ v (3)² +4()

Which expression is equivalent to the one that is modeled? a) 3x + 4 b) 3(3x + 4) c) 3(x + 4) d) 4(x + 3)