If p and q are two non zero numbers and 18(p+q) = 918+p)q, which of the following must be true?

If p and q are two non zero numbers and 18(p+q) = 918+p)q, which of the following must be true?

Answer Details

Using substitution If 18(p+18) = (18 + p)q
let q = 18
imply 18(p+18) = (18+p)18
i.e 18p + 18 x 18 = 18 x 18 + 18p
Since the left hand side = the right hand side
imply that q = 18