Rezolvati ecuatia in multimea N,efectuand si verificarea

Răspuns:
d) 5y=18
y=18÷5
y=3.6
5×3.6=18
g) 9x-1=0
9x=1
x=1:9
x=0.(1)
h) 4x-20=0
4x=20
x=20:4
x=5
4×5-20=20-20=0