Question No.1 ) In an examination 150 students secured first class in English and mathematics. 115 students secured first class in mathematics . How many students secured first class in English only ??

Don't spam
Need Genuine Answer .
Don't copy from Another website .

¤ 35 Students secured First Class in english only .

▪No of students who secured first class in Mathematics = n ( Math ) = 115 .

▪No of students who secured first class in English = n ( Eng ) = _?__.

▪No of students Secured first class in Eng & Math = n ( Eng U Math ) = 150 .

▪No of students who secured who secured first class in English only = n ( Eng - Math ) .

•n ( E - M ) = n ( E U M ) - n ( M ) - n ( E )

=》150 - 115 = 35

{x = -1/2 ,   y = -1

step-by-step explanation:

solve the following system:

{2 x + y = -2

{10 x - 3 y = -2

in the first equation, look to solve for y:

{2 x + y = -2

{10 x - 3 y = -2

subtract 2 x from both sides:

{y = -2 x - 2

{10 x - 3 y = -2

substitute y = -2 x - 2 into the second equation:

{y = -2 x - 2

{10 x - 3 (-2 x - 2) = -2

10 x - 3 (-2 x - 2) = (6 x + 6) + 10 x = 16 x + 6:

{y = -2 x - 2

{16 x + 6 = -2

in the second equation, look to solve for x:

{y = -2 x - 2

{16 x + 6 = -2

subtract 6 from both sides:

{y = -2 x - 2

{16 x = -8

divide both sides by 16:

{y = -2 x - 2

{x = -1/2

substitute x = -1/2 into the first equation:

{y = -1

{x = -1/2

collect results in alphabetical order:

answer:   {x = -1/2 ,   y = -1