Question

lf 5x-3y=9 and 3x-5y=7 then find (x-y)​

Answer 1

Answer:

3x+5y=7

Therefore: 3x+5y+2=9

Because both equations now equal 9, we can set them equal to each other.

5x+3y=3x+5y+2

simplify to get 2x-2y=2

2x=2y+2

x=y+1

Now substitute y+1 for x in one of the original equations.

5(y+1)+3y=9

5y+5+3y=9

8y+5=9

8y=4

y=0.5

Now plug 0.5 in for y and solve for x

3x+5(0.5)=7

3x+2.5=7

3x=4.5

x=1.5

Now simply add x and y together to get your answer.

1.5+0.5= 2

x+y= 2