Question

The pie chart below shows the annual sales of the last year from five different section of a
department store
What percentage of the annual sales comes from the household section?
b) Which section had the highest sales?
c) What fraction of the annual sales comes from the electronics
section?
d) The total annual sales from these 5 sections were 80 lakh.
What amount of this came from the garments and
furniture section?
Household
Electronics
15%

Garments
Food
30%​

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.