Question

5a-4b - c = 8 4a+2b - c = 2 3a + 4b +3c -16​

Answer 1

Explanation:

5a - 4b - c = 8

4a + 2b - c = 2

3a + 4b + 3c = -16

by adding equation 1 and 2 we get

8a + 2c = -8

4a + c = -4

c = -4 - 4a

now substitute c in the 2nd equation

4a + 2b +4 + 4a = 2

8a + 2b = -2

4a + b = -1

b = -1 - 4a

we have b and c in terms of a, now let's find a

5a - 4(-4-4a) - (-1 - 4a) = 8

5a + 16 + 16a + 1 + 4a =8

25a = -9

a = -9/25

b = -1 - 4(-9/25)

b= -1+36/25=11/25

c=-4 -4a = -4 +36/25=-53/25