Question

Almaz has taken two tests. Her average score is 7 ( out of ten ). The product of her scores is 45. What did she score in each test

Answer 1

Let the scores be x and y.

x+y/2 = 7

x+y = 14

xy = 45

x-y = √(x+y)²-4xy = √196-180 = √16 = 4

Adding,

2x = 18          x=18/2=9     y = 14-9=5

Thus, marks are 9 and 5

Answer 2

Let the scores be x and y

x+y/2=7

x=14-y

xy=45

(14-y)y=45

14y-y^2=45

y^2-14y+45=0

y^2-9y-5y+45=0

y(y-9)-5(y-9)=0

y=9 or 5

x=5 or 9

#BAL #answerwithquality