85700, 8570, 857, 85.7, 8.57, .857
Answer:
0.67 cm/s
Step-by-step explanation:
The area of a square is given by :
....(1)
Where
x is the side of a square

Differentiating equation (1) wrt t.

When A = 81cm², the side of the square, x = 9 cm
Put all the values,

So, the length of the side of a square is changing at the rate of 0.67 cm/s.
Answer is C
hope this helps!
To factor first multily 100 and 1 and get 100
then find what 2 numbers multiply to get 100 and add to get 20
the numbers are 10 and 10
so
split the center term up
100x^2+10x+10x+1
group
(100x^2+10x)+(10x+1)
undistribute
(10x)(10x+1)+(1)(10x+1)
undistribute/reverse distributive property
(10x+1)(10x+1)
(10x+1)^2