Question

a+3b-2c+2(3/4a+1/5b-1/7c)=​

Answer 1

Step-by-step explanation:

hey mate....a+3b-2c+2(3/4a+1/5b-1/7c)=a+3b+2c = 3

a = 3-3b-2c

2. 2a-b-3c = -8

2(3-3b-2c)-b-3c = -8

6-6b-4c-b-3c = -8

6-7b-7c = -8

-7b-7c = -14 <--divide through by -7

b+c = 2

5a+2b+c = 9

5(3-3b-2c)+2b+c = 9

15-15b-10c+2b+c = 9

15-13b-9c = 9

-13b-9c = -6

3. b+c = 2

b = 2-c

4. -13b-9c = -6

-13(2-c)-9c = -6

5. -26+13c-9c = -6

-26+4c = -6

4c = 20

c = 5

6. b+c = 2

b-5 = 2

7. b+5 = 2

b = -3

8. a+3b+2c = 3

a+3(-3)+2(5) = 3

a-9+10 = 3

a+1 = 3

a = 2

The solution is a=2, b=-3, c=5