Question

Solve
x+y=15 ; 2x-y=3

Answer 1

Answer:

The answer is provided in the picture.

Answer 2

Given

We have given two Equations : x+y= 15 & 2x-y=3

To find

We have to find x and y

$\sf\huge\bold{\underline{\underline{{Solution}}}}$

We can solve the above given two linear equations through various ways .Here ,we solve through substitution method.

Simplest method

➙x+y= 15------(1)

➙2x-y=3-------(2)

Adding Equation 1 and 2

➙x+y+2x-y= 15+3

➙3x-y+y= 18

➙3x=18

➙x= 18÷3

➙x= 6

Put x 's value into equation 1

➙x+y= 15

➙6+y=15

➙y=15-6

y= 9

Check:

➙x+y= 15

➙6+9=15

Since,LHS = RHS(Verified)

Alternative Method:

➙x+y= 15------(1)

➙2x-y= 3-------(2)

From equation 1

x= 15-y-----(3)

Put Equation 3 into 2

➙2(15-y)-y= 3

➙30-2y-y=3

➙30-3y=3

➙-3y= 3-30

➙-3y= -27

➙y= -27÷-3

y= 9

Put y's value into equation 3

➙x= 15-y

➙x= 15-9

➙x= 6

x=6