Simplify 5a-6b+8c+9a-20c-b+6b-c

$5 a - 6 b + 8 c + 9 a - 20 c - b + 6 b - c$

Combine the opposite terms in $5 a - 6 b + 8 c + 9 a - 20 c - b + 6 b - c$ .

Add $- 6 b$ and $6 b$ .

$5 a + 8 c + 9 a - 20 c - b + 0 - c$

Add $5 a + 8 c + 9 a - 20 c - b$ and $0$ .

$5 a + 8 c + 9 a - 20 c - b - c$

Add $5 a$ and $9 a$ .

$14 a + 8 c - 20 c - b - c$

Subtract $20 c$ from $8 c$ .

$14 a - 12 c - b - c$

Subtract $c$ from $- 12 c$ .

$14 a - b - 13 c$