Daca a/2=b/3=c/4 si 4a+2b-3c=30 sa se afle A B C. Va rog sa ma ajutati.

Răspuns :

a/2=b/3=c/4=k

a=2k

b=3k

c=4k

4a+2b-3c=30

4×2k+3×3k-3×4k=30

8k+9k-12k=30

17k-12k=30

5k=30

k=30:5

k=6

a=2×6

a=12

b=3×6

b=18

c=4×6

c=24


Salut !

[tex] \frac{a}{2} = \frac{b}{3} = \frac{c}{4} = > a = 2k;b = 3k;c = 4k[/tex]

[tex]4a + 2b - 3c = 30[/tex]

[tex]8k + 9k - 12k = 30[/tex]

[tex]17k - 12k = 30[/tex]

[tex]5k = 30[/tex]

[tex]k = 30:5 = 6[/tex]

[tex] = > a = 6 \times 2 = 12[/tex]

[tex] = > b = 6 \times 3 = 18[/tex]

[tex] = > c = 6 \times 4 = 24[/tex]

...................