Answer and explanation:
We add both equations to get a simultaneous equation
y+4z=16
2y+5z=32
We solve the equations using elimination method:
Multiply equation 1 by 5 and equation 2 by 4 to cancel out z
5y+20z=80
8y+20z=160
-3y=-80
Y=26.7
Substitute y=26.7 in equation 1
26.7+4z=16
4z=16-26.7
z= -2.67
y+z=26.7+(-2.67)= 24.03