Given expression is x² - 121
This is called Difference of Squared terms, we have a formula that is given as :-
a² - b² = (a - b) · (a + b)
Now using the above formula in the given expression, we get :-
x² - 121
x² - (11)²
here a = x and b = 11
x² - (11)² = (x - 11) · (x + 11)
but it says that student gave the answer as (x - 11) · (x - 11).
So, student's answer should be (x - 11) · (x + 11) instead of product of two (x - 11) terms.
B. 12 guest per table all you need to do it’s divide 216 and 18
Answer: 12 sqrt(5)
Explanation:
First simplify:
= Sqrt(45)
= sqrt(9*5) sqrt of 9 is 3 so bring out 3
= 3sqrt(5)
= 2sqrt(20)
= 2sqrt(4*5) sqrt of 4 is 2 so bring that out and multiply it by 2
= 4sqrt(5)
= 5 sqrt(5) is already simplified
= 3sqrt(5) + 4 sqrt(5) + 5sqrt(5)
= 12 sqrt(5)