Question

Ex 19 va rog pana la ora 15 dau coroana ....

Answer 1

(2a+2)×3:4=18×7
(2a+2)×3:4=126
(2a+2)×3=126×4
(2a+2)×3=504
(2a+2)=504:3
2a+2=168
2a=168-2
2a=166
a=166:2
a=83

(a+2×8)×9-(3×2+49)×5=103
(a+16)×9-(6+49)×5=103
(a+16)×9-55×5=103
(a+16)×9-275=103
(a+16)×9=103+275
(a+16)×9=378
a+16=378:9
a+16=42
a=42-16
a=26

[(2a+178)×15+90]=630×45
[(2a+178)×15+90]=28350
(2a+178)×15=28350-90
(2a+178)×15=28260
2a+178=28260:15
2a+178=1884
2a=1884-178
2a=1706
a=1706:2
a=853