Which distance measures 7 units? the distance between points l and m the distance between points l and n the distance between points m and n the distance between points m and p

How do i simply this expression (quadratic formula basis) on a ti-84 or normal calculator?

Which of the following equations is equivalent to x/3-6/x=1

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.