13. 81.64
14. 803.84
15. 153.83
16. 753.6
you just use circumference and area formulas for a circle
This conjecture is false, A and C don't have to be complementary angles.
Let Angle A be 100 and Angle B be 80 degrees. They are supplementary (sum of 180).
Let Angle C be 100 and Angle B is still 80 degrees. They are supplementary.
However, Angle A and Angle C are not complementary (sum of 90).
By "y = −9x2 − 2x" I assume you meant <span>y = −9x^2 − 2x (the "^" symbol represents exponentiation).
Let's find the first derivative of y with respect to x: dy/dx = -18x - 2. This is equivalent to the slope of the tangent line to the (parabolic) curve. Now let this derivative (slope) = 0 and solve for the critical value: -18x - 2 = 0, or
-18x = 2. Solving for x, x = -2/18, or x = -1/9.
When x = -1/9, y = -9(-1/9)^2 - 2(-1/9). This simplifies to y = -9/9 + 2/9, or
y = -7/9.
The only point at which the tangent to the curve is horiz. is (-1/9,-7/9).</span>
Answer:
there are only 4 whole numbers whose squares and cubes have the same number of digits.
Explanations:
let 0, 1, 2 and 4∈W (where W is a whole number), then
, 
,
, 
,
, 
,
, 
.
You can see from the above that only four whole numbers are there whose squares and cubes have the same number of digits
the answer is 10 hoped this helped have a great day
