Question

1. Find the buying price of each of the following when 5% ST is added on the purchase of. (a) A TV at ₹12,000​

Answer 1

x = 4, y – 3, z = 2

⇒ 4x2 + y2 + 25z2 + 4xy – 10yz – 20zx

= (2x)2 + (y)2 + (5z)2 + 2 x2 x x y-2 x y x 5z – 2 x 5z x 2x

= (2x + y- 5z)2

= (2 x 4 + 3- 5 x 2)2

= (8 + 3- 10)2

= (11 – 10)2

= (1)2 = 1