Question

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

7

16

9

2

Required​

Answer 1

Let's solve for x.

5x+3y=7x+y[/tex]

• Step 1: Add -7x to both sides.

$\tt 5x+3y+−7x=7x+y+−7x$

$\tt−2x+3y=y$

• Step 2: Add -3y to both sides.

$\tt −2x+3y+−3y=y+−3y−2x=−2y$

Step 3: Divide both sides by

$\tt -2.−2x−2=−2y−2x=y$

• Answer:

$\sf{\green{\underline{\underline{\orange{x=y -}}}}}$

Answer 2

Answer:

x+y = 2

Step-by-step explanation:

Given,

3x + 5y = 9  ---------------- (1)

5x + 3y = 7  ---------------- (2)

(1)*5 - (2)*3 =>

15x + 25y - (15x+9y) = 45 - 21

15x + 25y - 15x - 9y = 24

25y- 9y = 24

16y = 24

4y = 6

=> y = 3/2

substitute y = 3/2 in (1)

3x + 5(3/2) = 9

=> 3x + 15/2 = 9

=> (6x+15)/2 = 9

=> 6x+15 = 18

=> 6x = 18-15

=> 6x = 3

=> x = 3/6

=> x = 1/2

so, x+y = (1/2) + (3/2)

            = (1+3)/2

            = 4/2

            = 2