How do I solve systems of equations?

y=5x-8 5y=2x+6

Cora bought a package of erasers. there are 4 pink erasers and 12 blue erasers. what is the ratio of pink erasers to blue erasers?

The cone in the diagram has the same height and base area as the prism. what is the ratio of the volume of the cone to the volume of the prism? h hl base area-b base area =b volume of cone_1 volume of prism 2 volume of cone 1 volume of prism 3 volume of cone 2 volume of prism 3 oc. od. volume of cone volume of prism e. volume of cone volume of prism 3 2

When solving this problem: 3025/5.5 = a/90.75 you get 49912.5 which would be the length of one of the sides of a square when the area is only 90.75 inches. is that answer correct, why, and how is it possible?