Question

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

Answer 1

Step-by-step explanation:

5(3x+5y=9)

3(5x+3y=7)

15x+25y=45

15x+9y=21 by solving it

25y-9y=24

16y=24 2y=3

y=3/2

substitute y=3/2 in eqn2

5x+3y=7

5x+3(3/2)=7

5x+9/2=7

5x=7-9/2. take LCM as2

5x=14-9/2

x=1/2

X+y= 1/2+3/2

X+y=4/2

X+y=2