How many pairs of intersecting line segments are shown?

Two variables, x and y, vary inversely, and x=12 when y=4. what is the value of y when x=3?

The tile along the edge of a triangular community pool needs to be replaced? ?

Determine if the solution set for the system of equations shown is the empty set, contains one point or is infinite. x + y = 5 x + y = 7 {} 1 solution infinite