Question #6a4c5

1 Answer
Feb 4, 2017

#y^2 - 22y + 121 = (y - 11)(y- 11)#

Explanation:

#y^2 -22y+121#

By splitting the middle term i.e. -22 in such a way so, that the sum of those two numbers would be -22 and their product would be 121. Therefore, these two numbers are -11 and -11 . Here, both conditions are applied.

#y^2 - 11y - 11y + 121#

#y(y - 11) - 11(y -11)#

#(y - 11)(y- 11)#

Alternative Method:

#y^2 - 22y + 121#

By using the identity -

#(a - b)(a - b) = a^2 - 2ab + b^2#

Here , #a = y , b = 11#

#(y)^2 - 2(y)(11) + (11)^2#

#(y - 11)(y -11)#