Let's solve each of the polynomial multiplication problems step by step. The goal is to
distribute the monomial outside the parentheses to each term inside the parentheses, then simplify.
---
1) $ 3u^2(3u^2 + 5u - 7u^2 + 12) $
First, simplify inside the parentheses:
$$
3u^2 + 5u - 7u^2 + 12 = (3u^2 - 7u^2) + 5u + 12 = -4u^2 + 5u + 12
$$
Now distribute $ 3u^2 $:
$$
3u^2(-4u^2) + 3u^2(5u) + 3u^2(12) = -12u^4 + 15u^3 + 36u^2
$$
✔ Answer: $ -12u^4 + 15u^3 + 36u^2 $
---
2) $ -5c^2(-4c^6 + 8c^4 + 10) $
Distribute $ -5c^2 $ to each term:
$$
-5c^2(-4c^6) = 20c^8 \\
-5c^2(8c^4) = -40c^6 \\
-5c^2(10) = -50c^2
$$
✔ Answer: $ 20c^8 - 40c^6 - 50c^2 $
---
3) $ 7a^2(-4a - 6a^3) $
Distribute $ 7a^2 $:
$$
7a^2(-4a) = -28a^3 \\
7a^2(-6a^3) = -42a^5
$$
✔ Answer: $ -42a^5 - 28a^3 $
---
4) $ 9n(-2n^3 + 6n^5 - 7n^2) $
Distribute $ 9n $:
$$
9n(-2n^3) = -18n^4 \\
9n(6n^5) = 54n^6 \\
9n(-7n^2) = -63n^3
$$
Now arrange in descending order:
$$
54n^6 - 18n^4 - 63n^3
$$
✔ Answer: $ 54n^6 - 18n^4 - 63n^3 $
---
5) $ -x^5(1 + 17x^6) $
Distribute $ -x^5 $:
$$
-x^5(1) = -x^5 \\
-x^5(17x^6) = -17x^{11}
$$
✔ Answer: $ -17x^{11} - x^5 $
---
6) $ 8y^3(y^4 + 11) $
Distribute $ 8y^3 $:
$$
8y^3(y^4) = 8y^7 \\
8y^3(11) = 88y^3
$$
✔ Answer: $ 8y^7 + 88y^3 $
---
7) $ -b^7(4b^6 + 8b^4 + 2b + 9) $
Distribute $ -b^7 $:
$$
-b^7(4b^6) = -4b^{13} \\
-b^7(8b^4) = -8b^{11} \\
-b^7(2b) = -2b^8 \\
-b^7(9) = -9b^7
$$
✔ Answer: $ -4b^{13} - 8b^{11} - 2b^8 - 9b^7 $
---
8) $ 10(7m^2 - 3 - m^3) $
First, rewrite in standard form: $ -m^3 + 7m^2 - 3 $
Now distribute $ 10 $:
$$
10(-m^3) = -10m^3 \\
10(7m^2) = 70m^2 \\
10(-3) = -30
$$
✔ Answer: $ -10m^3 + 70m^2 - 30 $
---
✔ Final Answers:
1) $ -12u^4 + 15u^3 + 36u^2 $
2) $ 20c^8 - 40c^6 - 50c^2 $
3) $ -42a^5 - 28a^3 $
4) $ 54n^6 - 18n^4 - 63n^3 $
5) $ -17x^{11} - x^5 $
6) $ 8y^7 + 88y^3 $
7) $ -4b^{13} - 8b^{11} - 2b^8 - 9b^7 $
8) $ -10m^3 + 70m^2 - 30 $
Let me know if you'd like these explained with visual steps or diagrams!
Parent Tip: Review the logic above to help your child master the concept of polynomial multiplication worksheet.