This is a system. put the first equation under the second one and subtract. y - y = 0. 2x - 3x = -x. 1 - (-4) = 5. so the result is 0 = -x +5 or x = 5. plug x into either equation and y = 11. the answer is (5, 11).
Thickness of the plate before polishing = 2.342 Thickness of the plate after polishing. = 2.087 How much was removed = 2.342- 2.087 = 0.255 Hence , the answer 0.255 which is option B