Two shopkeepers sell electronic goods of same kind .their sales for he two items are represented by two equations 3x+y=9and 7x+2y=20.find the sale price of each item by the two shopkeepers.

Asked by anshika adlakha | 24th Jun, 2014, 04:50: PM

Expert Answer:

C o n s i d e r space t h e space s y s t e m space o f space e q u a t i o n s 3 x plus y equals 9 space.... left parenthesis 1 right parenthesis a n d 7 x plus 2 y equals 20.... left parenthesis 2 right parenthesis M u l t i p l y i n g space t h e space e q u a t i o n left parenthesis 1 right parenthesis space b y space 2 space a n d space s u b t r a c t i n g space f r o m space left parenthesis 2 right parenthesis comma space w e space h a v e space space space space 7 x plus 2 y equals 20 bottom enclose minus 6 x minus 2 y equals minus 18 end enclose space space space space space x space space space space space space space space space space equals space 2 S u b s t i t u t i n g space t h e space v a l u e space x equals 2 space i n space e q u a t i o n space left parenthesis 1 right parenthesis comma space w e space h a v e 3 cross times 2 plus y equals 9 rightwards double arrow 6 plus y equals 9 rightwards double arrow y equals 9 minus 6 rightwards double arrow y equals 3 T h u s comma space t h e space s a l e space o f space t w o space i t e m s space a r e space 2 space a n d space 3

Answered by Vimala Ramamurthy | 25th Jun, 2014, 09:07: AM