Helppp with part (b) will mark brainlest

Which equation can be used to measure the density of water in a spherical water tank? let w represent the number of water particles within the region.

A)a square brown tarp has a square green patch green in the corner the side length of the tarp is (x + 8) and the side length of the patch is x what is the area of the brown part of the tarpb)a square red placemat has a gold square in the corner the side length of the gold square is (x - 2) inches with the width of the red region is 4 in what is the area of the red part of the placemat

y=2x−1 5x−4y=1 is (1,1)(1,1) a solution of the system?