Question

3x+5y=9 and 5x+3y=7 then what is the value of x+y?

Answer 1

Answer:

2

Step-by-step explanation:

Adding the two equation give

( 3x + 5y ) + ( 5x + 3y ) = 9 + 7

=> 8x + 8y = 16

=> 8 ( x + y ) = 16

=> x + y = 2

Answer 2

Answer:

X + y = 2

Step-by-step explanation:

3x+5y=9 …(1)

5x+3y=7 …(2)

Let us simplify the equations by eliminating a variable

Make the coefficients of X or Y equal

Multiply equation (1) with 5 and equation (2) with 3

We get 15x+25y=45 and 15x+9y=21

Now subtract the equations, we get

(15x+25y)-(15x+9y)=(45–21)

16y=24, y= 24/16 = 3/2

Substituting the value of y in equation (1) we get

3x+5(3/2)=9

3x+15/2=9

3x=9–15/2

3x=3/2

x =1/2

x+y =3/2+1/2= 2

x+y=2