Question

Rohit purchased 4 dozen copies at the rate of Rs. 18 per dozen on decreasing the market rate, he sold 3 dozen and remaining I dozen at Rs. 16.50 per dozen. Find his loss %?
Answer opption
a) 10 5/12 % b) 10 6/13 % c) 10 7/12 % d) 10 4/9 %




please give answer quickly...
​

Answer 1

Answer:

This implies that

x2+2ax=4x−4a−13

or

x2+2ax−4x+4a+13=0

or

x2+(2a−4)x+(4a+13)=0

Since the equation has just one solution instead of the usual two distinct solutions, then the two solutions must be same i.e. discriminant = 0.

Hence we get that

(2a−4)2=4⋅1⋅(4a+13)

or

4a2−16a+16=16a+52

or

4a2−32a−36=0

or

a2−8a−9=0

or

(a−9)(a+1)=0

So the values of a are −1 and 9.

Answer 2

Answer:

i don't know how to solve and iam right