C or the third one because you have to make the Y by itself and drag the X to the opposite side of the = sign. The x turns to a negative because the sign changes when it switches places. Then when 7y is by itself, you divide everything by 7 so, 7y/7= -3x/7 + 28/7 . You simplify each. 7y/7 cancels down to y. -3x/7 stays the same because it is the slope. 28/7 is 4 because you divide. So you get y= -3x/7 + 4 .
This equation means that you mustfind the height which in this case is W. ok in order to find w you must do the opposite equation to the output so divide 183 by 212 and the answer is W so W=.9 ( im only in 9th grade so this may or may not be correct)