Answer:
It is a linear equation
solving by substitution method
x + y =6 ------ eqn 1
2x + 4y =20 -------- eqn 2
x = 6 - y ------ eqn 3
putting the value of x from eqn 3. into eqn 2.
2(6-y) +4y =20
12 - 2y + 4y =20
12 +2y =20
2y = 20-12
2y = 8
2y / 2 =8/2
y =4
put the value of y into eqn 3
x =6 - y
x = 6 - 4
x = 2
Therefore x = 2, y= 4