Question

1. $n - 4 - 9$
2. $4n - n$
3. $-3x - 9 + 15x$
4. $-9k + 8k$
5. $-16n - 14n$
6. $15n - 19n$
7. $-4 + 7(1 - 3m)$
8. $-5n + 3(6 + 7n)$
9. $-2n - (9 - 10n)$
10. $10 - 5(9n - 9)$
11. $9a + 10(6a - 1)$
12. $-9(6m - 3) + 6(1 + 4m)$
13. $-10(1 - 9x) + 6(x - 10)$
14. $5(-2n + 4) + 2(n + 3)$
15. $-3(10b + 10) + 5(b + 2)$
16. $-7(n + 3) - 8(1 + 8n)$

Explanation:

Step1: Combine constant terms

$n + (-4 - 9) = n - 13$

Step2: Combine like terms

$4n - n = (4-1)n = 3n$

Step3: Combine x terms first

$-3x + 15x - 9 = (15-3)x - 9 = 12x - 9$

Step4: Combine like k terms

$-9k + 8k = (-9+8)k = -k$

Step5: Combine like n terms

$-16n -14n = (-16-14)n = -30n$

Step6: Combine like n terms

$15n -19n = (15-19)n = -4n$

Step7: Distribute then combine terms

$-4 + 7(1) -7(3m) = -4 +7 -21m = 3 -21m$

Step8: Distribute then combine terms

$-5n +3(6)+3(7n) = -5n +18 +21n = 16n +18$

Step9: Remove parentheses then combine terms

$-2n -9 +10n = (-2+10)n -9 = 8n -9$

Step10: Distribute then combine terms

$10 -5(9n)+5(9) = 10 -45n +45 = 55 -45n$

Step11: Distribute then combine terms

$9a +10(6a)-10(1) = 9a +60a -10 = 69a -10$

Step12: Distribute then combine terms

$-9(6m)+9(3)+6(1)+6(4m) = -54m +27 +6 +24m = -30m +33$

Step13: Distribute then combine terms

$-10(1)+10(9x)+6(x)-6(10) = -10 +90x +6x -60 = 96x -70$

Step14: Distribute then combine terms

$5(-2n)+5(4)+2(n)+2(3) = -10n +20 +2n +6 = -8n +26$

Step15: Distribute then combine terms

$-3(10b)-3(10)+5(b)+5(2) = -30b -30 +5b +10 = -25b -20$

Step16: Distribute then combine terms

$-7(n)-7(3)-8(1)-8(8n) = -7n -21 -8 -64n = -71n -29$

Answer:

1. $\boldsymbol{n - 13}$
2. $\boldsymbol{3n}$
3. $\boldsymbol{12x - 9}$
4. $\boldsymbol{-k}$
5. $\boldsymbol{-30n}$
6. $\boldsymbol{-4n}$
7. $\boldsymbol{3 - 21m}$
8. $\boldsymbol{16n + 18}$
9. $\boldsymbol{8n - 9}$
10. $\boldsymbol{55 - 45n}$
11. $\boldsymbol{69a - 10}$
12. $\boldsymbol{-30m + 33}$
13. $\boldsymbol{96x - 70}$
14. $\boldsymbol{-8n + 26}$
15. $\boldsymbol{-25b - 20}$
16. $\boldsymbol{-71n - 29}$