It is 100 times smaller because 1.95x100=195 !!!
Cross multiply:-
3(b - 2) = (2b - 5)(b + 2)
3b - 6 = 2b^2 + 4b - 5b - 10
2b^2 - 4b - 4 = 0
b^2 - 2b - 2 = 0
b = 2.73, -0.73 Answer
78.5= (3.14)r^2
25=r^2
5=r
So, the radius of a circle with an area is 78.5 cm^2 is 5 cm^2
I suppose you mean

Differentiate one term at a time.
Rewrite the first term as

Then the product rule says

Then with the power and chain rules,

Simplify this a bit by factoring out
:

For the second term, recall that

Then by the chain rule,

So we have

and we can simplify this by factoring out
to end up with
