Question

19. Află valoarea lui a:
(2 x a + 2) x 3:4:7 = 18
[a + (14 : 7) x 8] x 9 - [15: 5 x 2 + (147 : 3)] x 5 = 103
[(2 x a + 178) x 15 + 90] : 45 = 630 VA ROG E Urgent​

Answer 1

(2xa+2)X3:4:7=18
(2xa+2)x3:4=18x7
(2xa+2)X3:4=126
(2xa+2)X3=126x4
(2xa+2)X3=504
2xa+2=504:3
2xa+2=168
2xa=168-2
2xa=166
A=166:2
A=84


[a+(14:7)x8]x9-[15:5x2+(147:3)]x5=103
[a+2x8]x9-[3x2+49]x5=103
(A+16)x9-(6+49)X5=103
(A+16)x9-55x5=103
(A+16)x9-275=103
(A+16)x9=103+275
(A+16)x9=378
A+16=378:9
A+16=42
A=42-16
A=24

[(2xa+178)x15+90]:45=630
[(2xa+178)x15+90]=630x45
[2xa+178)x15+90]=28350
(2xa+178)x15=28350-90
(2xa+178)x15=28260
2xa+178=28260:15
2xa+178=1884
2xa=1884-178
2xa=1706
A=1706:2
A=853

Succes! Sper ca te am ajutat