Advertisements
Advertisements
Question
Factorise the following.
y2 + 4y – 21
Sum
Advertisements
Solution
We have,
y2 + 4y – 21
= y2 + (7 – 3)y – 21
= y2 + 7y – 3y – 21
= y(y + 7) – 3(y + 7)
= (y + 7)(y – 3)
shaalaa.com
Is there an error in this question or solution?
Chapter 7: Algebraic Expression, Identities and Factorisation - Exercise [Page 235]
APPEARS IN
RELATED QUESTIONS
Expand (2)2p − 3q
Factorise the following expressions
y2 – 10y + 25
(a – 1)2 = a2 – 1
Evaluate the following, using suitable identity
9982
(a – b)2 + ______ = a2 – b2
Factorise the following, using the identity a2 – 2ab + b2 = (a – b)2.
x2 – 8x + 16
Factorise the following, using the identity a2 – 2ab + b2 = (a – b)2.
9x2 – 12x + 4
Factorise the following.
x2 – 10x + 21
Factorise the following.
x2 – 17x + 60
If x – y = 13 and xy = 28, then find x2 + y2.
