Question

if 3x+5y=9; 5x+3y=7 find x-y​

Answer 1

Answer:

HELLO DEAR,

3X + 5Y = 9 -------------(1)

5X +3Y = 7 ----------------(2)

SUBTRACTING---(1) from----(2)

we get

3x+5y = 9

5x+3y = 7

(-)_(-)___(-)

——————

-2x +2y = 2

=> -x + y = 1----------(3)

adding ---(2) and --(1)

3x +5y = 9

5x +3y = 7

——————

8x + 8y = 16

=> x + y = 2----------(4)

from--(3) and ---(4)

we get,

-x + y = 1

x + y = 2

————

2y = 3

=> y = 3/2 Put in --(3)

we get,

-x +3/2 = 1

=> x = 3/2 - 1

=> x = (3-2)/2

=> x = 1/2

Step-by-step explanation:

Answer 2

3x + 5y = 9

solve for x : 3x = 9 - 5y

3x / 3 = 9 - 5y / 3

x = 9 - 5y / 3

x = - 5y / 3 + 3

solve for y : 5y = 9 - 2x

5y / 5 = 9 - 3x / 5

y = 9 - 3x / 5

5x + 3y = 7

solve for x : 5x = 7 - 3y

5x / 5 = 7 - 3y / 5

x = 7 - 3y / 5

solve for y : 3y = 7 - 5x

3y / 3 = 7 - 5x / 3

y = 7 - 5x / 3