Which expression gives the x-coordinate of the solution of the system?
{2x + 3y = 5
{3x + 5y = 7
(it's one big bracket.)

which expression gives the y-coordinate of the solution of the system?
{2x + y = 2
{3x + 4y = -22

and

which expression shows the solution of the system?
{5x + 4y = 2
{-2y = 8 + 4x

1) the x-coordinate of the system can be given as follow:
2x+3y = 5  (i)
3x+5y =7    (ii)
we  multiply (i) by 5 and (ii)  by 3, we have
 10x+15y = 25 (a)
  9x+15y =21   (b)
so (a) - (b) implies  x = 4,

2) We do the same method for
{2x + y = 2
{3x + 4y = -22,

and we found y = -10,
3) for the last one,
{5x + 4y = 2
{-2y = 8 + 4x
this system is equivalent to
{5x + 4y = 2  (i)
{4x + 2y = - 8  (ii)
so, multiply  (i) by 4 and (ii) by 5, and we have
20x + 16y = 8  (a)
20x +  10y = -40  (b)
elimination of x gives  6y = 48 then y= 8, we can find x fastly by replacing y=8 in (i), so 5x +4(8) =2, which implies  x= -6
finally the solution is S= {(-6, 8)}
 
 

If gravity is one third on mars then weight also one third on mars