Question

Which expression is equivalent to (4 + 7i)(3 + 4i)?

Answer 1

Weight of B = (A + B)’s weight + (B + C)’s weight – (A + B + C)’s weight

= 40 \times 2 + 43 \times 2 – 45 \times 3

= 80 + 86 – 135 = 31 kg.

Hence option [D] is correct answer.

Answer 2

Weight of B = (A + B)’s weight + (B + C)’s weight – (A + B + C)’s weight= 40 \times 2 + 43 \times 2 – 45 \times 3= 80 + 86 – 135 = 31 kg.

It is taking place by complex division that should denote the solution to conjugate the terms and denominator.