Which is the correct for of the equation 4x-3y=21 when solved for y

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36

Which equation represents the model shown? a)1/3 divide 1/6 = 2 b)2/3 divide 1/6 = 2/18 c)1/3 divide 1/6 = 1/18 d)2/3 divide 1/6 =4

Table which ratio is equivalent to 3: 7? 6: 7 3: 21 24: 56 15: 30