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.
Consider re-writing this formula as "A = pi*r^2." The backslash symbol "\" is unnecessary.
If A = pi*r^2, and we wish to solve for r, then divide both sides by pi:
A/pi = r^2
Taking the square root of both sides, sqrt(A/pi) = r (r must be positive in this situation).
Answer:
1.
centre(h,k)=(-13,9)
radius (r)=6
we have
equation of the circle is
(x-h)²+(y-k)²=r²
(x+13)²+(y-9)²=6²
x²+26x+169+y²-18y+81=36
x²+y²+26x-18y+169+81-36=0
x²+y²+26x-18y +214=0
is a required equation of the circle.
2.
centre(h,k)=(1,-1)
radius (r)=11
we have
equation of the circle is
(x-h)²+(y-k)²=r²
(x-1)²+(y+1)²=11²
x²-2x+1+y²+2y+1=121
x²+y²-2x+2y=121-2
x²+y²-2x+2y=119
is a required equation of the circle.
Answer:
Step-by-step explanation:
Here so u can give that person brainliest
Answer:
192
Step-by-step explanation:
To find how many phones are expected to be defective, we need to represent the values in a fraction.

x = number of defective phones
Now we can solve this using algebra.
To get the value of x we need to multiply both sides by 8000 to leave x alone.



So around 192 cell phones are expected to be defective out of 8000 phones.