Question: Expand the following exressions. ① (x+2)(y+4) ② (x+4)(X+5) ③ (x+7)(x+7) ④ (x+4)(x-4) How to solve: ① can be expanded like this, (x+2)(y+4)=xy+4x+2y+8 ② We expand by using the formula, the quantity x plus a, close quantity, times the quantity x plus b, close quantity equals x squared plus t…