Question

X+y=20
x-y=16
Substitution

Answer 1

x+ y = 20

x - y = 16

= 2y = 20-16=4

y = 2

Applying the value:

x + y = 20

x + 2 = 20

x = 18

Answer 2

Explanation:

x+ y = 20

- x - y = 16

= 2y = 4

y = 2

put the value of y in any equation u like

x + y = 20

x + 2 = 20

x = 18