Problems 1-10 : Expand.
Problem 1 :
(y + 3)2
Problem 2 :
(2p + 3q)2
Problem 3 :
(5 + k2)2
Problem 4 :
(-x + 2)2
Problem 5 :
(1 + z3)2
Problem 6 :
(m - 5)2
Problem 7 :
(5k - 1)2
Problem 8 :
(4e - 5f)2
Problem 9 :
(4 - d2)2
Problem 10 :
(p2 - q2)2
Problems 11-14 : Expand.
Problem 11 :
(m + n)(m - n)
Problem 12 :
(x + 3)(x - 3)
Problem 13 :
(c2 + 2d)(c2 - 2d)
Problem 14 :
(7 + y)(7 - y)
Problem 15 :
A square koi pond is surrounded by a gravel path. Write an expression that represents the area of the path.
1. Answer :
Use the rule for (a + b)2.
(a + b)2 = a2 + 2ab + b2
Identify a and b : a = y and b = 3.
(y + 3)2 = y2 + 2(y)(3) + 32
= y2 + 6y + 9
2. Answer :
Use the rule for (a + b)2.
(a + b)2 = a2 + 2ab + b2
Identify a and b : a = 2p and b = 3q.
(2p + 3q)2 = (2p)2 + 2(2p)(3q) + (3q)2
= 4p2 + 12pq + 9q2
3. Answer :
Use the rule for (a + b)2.
(a + b)2 = a2 + 2ab + b2
Identify a and b : a = 5 and b = k2.
(5 + k2)2 = 52 + 2(5)(k2) + (k2)2
= 25 + 10k2 + k4
4. Answer :
Use the rule for (a + b)2.
(a + b)2 = a2 + 2ab + b2
Identify a and b : a = -x and b = 2.
(-x + 2)2 = (-x)2 + 2(-x)(2) + 22
= x2 - 4x + 4
5. Answer :
Use the rule for (a + b)2.
(a + b)2 = a2 + 2ab + b2
Identify a and b : a = 1 and b = z3.
(1 + z3)2 = 12 + 2(1)(z3) + (z3)2
= 1 + 2z3 + z6
6. Answer :
Use the rule for (a - b)2.
(a - b)2 = a2 - 2ab + b2
Identify a and b : a = m and b = 5.
(m - 5)2 = m2 - 2(m)(5) + 52
= m2 - 10m + 25
7. Answer :
Use the rule for (a - b)2.
(a - b)2 = a2 - 2ab + b2
Identify a and b : a = 5k and b = 1.
(5k - 1)2 = (5k)2 - 2(5k)(1) + 12
= 25k2 - 10k + 1
8. Answer :
Use the rule for (a - b)2.
(a - b)2 = a2 - 2ab + b2
Identify a and b : a = 4e and b = 5f.
(4e - 5f)2 = (4e)2 - 2(4e)(5f) + (5f)2
= 16e2 - 40ef + 25f2
9. Answer :
Use the rule for (a - b)2.
(a - b)2 = a2 - 2ab + b2
Identify a and b : a = 4 and b = d2.
(4 - d2)2 = 42 + 2(4)(d2) + (d2)2
= 16 + 8d2 + d4
10. Answer :
Use the rule for (a - b)2.
(a - b)2 = a2 - 2ab + b2
Identify a and b : a = p2 and b = q2.
(p2 - q2)2 = (p2)2 + 2(p2)(q2) + (q2)2
= p4 + 2p2q2 + q4
11. Answer :
Use the rule for (a + b)(a - b).
(a + b)(a - b) = a2 - b2
Identify a and b : a = m and b = n.
(m + n)(m - n) = m2 - n2
12. Answer :
Use the rule for (a + b)(a - b).
(a + b)(a - b) = a2 - b2
Identify a and b : a = x and b = 3.
(x + 3)(x - 3) = x2 - 32
= x2 - 9
13. Answer :
Use the rule for (a + b)(a - b).
(a + b)(a - b) = a2 - b2
Identify a and b : a = c2 and b = 2d.
(c2 + 2d)(c2 - 2d) = (c2)2 - (2d)2
= c4 - 4d2
14. Answer :
Use the rule for (a + b)(a - b).
(a + b)(a - b) = a2 - b2
Identify a and b : a = 7 and b = y.
(7 + y)(7 - y) = 72 - y2
= 49 - y2
15. Answer :
Understand the Problem.
The answer will be an expression that represents the area of the path.
List the important information :
(i) The pond is a square with a side length of (x - 3).
(ii) The path has a side length of (x + 3).
Make a Plan.
The area of the pond is (x - 3)2. The total area of the path plus the pond is (x + 3)2. You can subtract the area of the pond from the total area to find the area of the path.
Solve.
Step 1 :
Find the total area.
Use the rule for (a + b)2.
(a + b)2 = a2 + 2ab + b2
Identify a and b : a = x and b = 3.
(x + 3)2 = (x)2 + 2(x)(3) + (3)2
= x2 + 6x + 9
Step 2 :
Find the area of the pond.
Use the rule for (a - b)2.
(a - b)2 = a2 - 2ab + b2
Identify a and b : a = x and b = 3.
(x - 3)2 = (x)2 - 2(x)(3) + (3)2
= x2 - 6x + 9
Step 3 :
Find the area of the path.
Area of Path = Total Area - Area of Pond
= (x2 + 6x + 9) - (x2 - 6x + 9)
Use the Distributive Property.
= x2 + 6x + 9 - x2 + 6x - 9
Group like terms together.
= (x2 - x2) + (6x + 6x) + (9 - 9)
Combine like terms.
= 12x
The area of the path is 12x.
Kindly mail your feedback to v4formath@gmail.com
We always appreciate your feedback.
©All rights reserved. onlinemath4all.com
Jan 11, 25 07:52 AM
Jan 10, 25 05:08 AM
Jan 10, 25 05:02 AM