Question

4x-3,42×10=65,6 ; (3a-15,66)×28=0 ; (17,4-5y)×15=3

Answer 1

4x=65.6+3.42×10
4x=65.6+34,2
4x=99.8
X=99.8:4
X=24.95
4×24.95-3.42×10=65.6

17.4×15-5y×15=3
261-75y=3
261-3=75y
258=75y
y=258:75
y=3.44
(17.4-5×3.44)×15=3

(3a-15.66)×28=0
3a×28-15.66×28=0
84a-438.48=0
84a=438.48
a=438.48:84
a=5.22
(3×5.22-15.66)×28=0