Please help me i dont understand

What is the vertex form of f(x) = x2 + 6x + 3

Can (3,5 and square root 34) be sides on a right triangle?

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.