Question 1. Find (GCF/HCF) of 2x2 and 12x2
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
2x2 = 2 * x * x
12x2 = 2* 2 * 3 * x * x
GCF(2x2, 12x2) = 2 * x * x
= 2x2
Question 2. Find (GCF/HCF) of 6x3y and 18x2y3
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
6x3y = 2 * 3 * x * x * x * y
18x2y3 = 2 * 2 * 3 * x * x * y * y * y
GCF(6x3y, 18x2y3) = 2 * 3 * x * x * y
= 6x2y
Question 3. Find (GCF/HCF) of 7x, 21x2 and 14xy2
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
7x = 7 * x
21x2 = 7 * 3 * x * x
14xy2 = 7 * 2 * x * y * y
GCF(7x, 21x2, 14xy2) = 7*x
= 7x
Question 4. Find (GCF/HCF) of 42x2yz and 63x3y2z3
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
42x2yz = 2 * 3 * 7 * x * x * y * z
63x3y2z3 = 3 * 3 * 7 * x * x * x * y * y * z * z * z
GCF(42x2yz, 63x3y2z3) = 3 * 7 * x * x * y * z
= 21x2yz
Question 5. Find (GCF/HCF) of 12ax2, 6a2x3 and 2a3x5
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
12ax2 = 2 * 2 * 3 * a * x * x
6a2x3 = 2 * 3 * a * a * x * x * x
2a3x5 = 2 * a * a * a * x * x * x * x * x
GCF(12ax2, 6a2x3,2a3x5) = 2 * a * x * x
= 2ax2
Question 6. Find (GCF/HCF) of 9x2, 15x2y3, 6xy2 and 21x2y2
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
9x2 = 3 * 3 * x * x
15x2y3 = 3 * 5 * x * x * y * y * y
6xy2 = 2 * 3 * x * y * y
21x2y2 = 3 * 7 * x * x * y * y
GCF(9x2, 15x2y3, 6xy2 and 21x2y2) = 3 * x
= 3x
Question 7. Find (GCF/HCF) of 4a2b3, -12a3b, 18a4b3
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
4a2b3 = 2 * 2 * a * a * b * b * b
-12a3b = -1 * 2 * a * a * a * b
18a4b3 = 2 * 3 * 3 * a * a * a * a * b * b * b
GCF(4a2b3, -12a3b, 18a4b3) = 2 * a * a * b
= 2a2b
Question 8. Find (GCF/HCF) of 6x2y2, 9xy3, 3x3y2
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
6x2y2 = 2 * 3 * x * x * y * y
9xy3 = 3 * x * y * y * y
3x3y2 = 3 * x * x * x * y * y
GCF(6x2y2, 9xy3, 3x3y2) = 3 * x * y * y
= 3xy2
Question 9. Find (GCF/HCF) of a2b3, a3b2
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
a2b3 = a * a * b * b * b
a3b2 = a * a * a * b * b
GCF(a2b3, a3b2) = a * a * b * b
= a2b2
Question 10. Find (GCF/HCF) of 36a2b2c4, 54a5c2, 90a4b2c2
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
36a2b2c4 = 2 * 2 * 3 * 3 * a * a * b * b * c * c * c * c
54a5c2 = 2 * 3 * 3 * 3 * a * a * a * a * a * c * c
90a4b2c2 = 2 * 3 * 3 * 5 * a * a * a * a * b * b * c * c
GCF(36a2b2c4, 54a5c2, 90a4b2c2) = 2 * 3 * 3 * a * a * c * c
= 18a2c2
Question 11. Find (GCF/HCF) of x3, -yx2
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
x3 = x * x * x
-yx2 = -1 * y * x * x
GCF(x3, -yx2) = x * x
= x2
Question 12. Find (GCF/HCF) of 15a3, -45a2, -150a
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
15a3 = 3 * 5 * a * a * a
-45a2 = -1 * 3 * 3 * 5 * a *a
-150a = -1 * 2 * 3 * 5 * 5 * a
GCF(15a3, -45a2, -150a) = 3 * 5 * a
= 15a
Question 13. Find (GCF/HCF) of 2x3y2, 10x2y3, 14xy
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
2x3y2 = 2 * x * x * x * y * y
10x2y3 = 2 * 5 * x * x * y * y * y
14xy = 2 * 7 * x * y
GCF(2x3y2, 10x2y3, 14xy) = 2 * x * y
= 2xy
Question 14. Find (GCF/HCF) of 14x3y5, 10x5y3, 2x2y2
Solution:
First Prime Factorize each monomial, then find common among them.
Here,
14x3y5 = 2 * 7 * x * x * x * y * y * y * y * y
10x5y3 = 2 * 5 * x * x * x * x * x * y * y * y
2x2y2 = 2 * x * x * y * y
GCF(14x3y5, 10x5y3, 2x2y2) = 2 * x * x * y * y
= 2x2y2
Find the greatest common factor(GCF) of the terms in the following expressions. (Q15 - Q17)
Question 15. 5a4 + 10a3 - 15a2
Solution:
Here, 5a4 = 5 * a * a * a * a
10a3 = 2 * 5 * a * a * a
-15a2 = -1 * 3 * 5 * a * a
5a4 + 10a3 - 15a2 = (5 * a * a * a * a) + (2 * 5 * a * a * a) + (-1 * 3 * 5 * a * a)
= 5a2(a2 + 2a - 3)
GCF(5a4 + 10a3 - 15a2) = 5a2
Question 16. 2xyz + 3x2y + 4y2
Solution:
Here, 2xyz = 2 * x * y * z
3x2y = 3 * x * x * y
4y2 = 2 * 2 * y * y
2xyz + 3x2y + 4y2 = (2 * x * y * z) + (3 * x * x * y) + (4 * y * y)
= y(2x + 3x2 + 4y)
GCF(2xyz + 3x2y + 4y2) = y
Question 17. 3a2b2 + 4b2c2 + 12a2b2c2
Solution:
Here, 3a2b2 = 3 * a * a * b * b
4b2c2 = 2 * 2 * b * b * c * c
12a2b2c2 = 2 * 2 * 3 * a * a * b * b * c * c
3a2b2 + 4b2c2 + 12a2b2c2 = (3 * a * a * b * b) + (2 * 2 * b * b * c * c) + (2 * 2 * 3 * a * a * b * b * c * c)
= b(3a2b + 4bc2 + 12a2bc2)
GCF(3a2b2 + 4b2c2 + 12a2b2c2) = b
Summary
Exercise 7.1 in the RD Sharma Class 8 textbook is designed to help students develop a strong foundation in factorizing linear expressions. The practice questions cover a wide range of scenarios, including expressions with a single variable, expressions with multiple variables, and expressions involving common factors. By working through these questions, students will learn to identify the appropriate factorization techniques, apply them correctly, and simplify the given expressions. Mastering the skills covered in this exercise will enable students to tackle more complex algebraic problems and lay the groundwork for further exploration of factorization concepts.