Question

X+y=10
X - y = 2

X + y = 20
X- y = 4 =

Answer 1

{X+y=10 =====> y=10-x
{X - y =2
------------ (+)
2x = 12
x = 6 ✓ ======> y=10-6 = 4 ✓

≠==========================

{X + y = 20 ==> y=20-x
{X- y = 4
---------------- (+)
2x = 24
x = 12 ✓ =====> y=20-12= 8 ✓