Answer:
8 π .
Step-by-step explanation:
radius increases at a constant rate of 1 in/sec.
dr / dt = 1
where r is radius .
radius after 4 sec
r = 1 x 4 = 4 in
area A = π r²
differentiating both sides
dA / dt = 2 π r dr / dt
Putting dr / dt = 1 , r = 4 in
dA / dt = 2 π x 4 x 1
= 8 π sq in per sec.
Area increases at the rate of 8 π per sec.
Answer:
False
Step-by-step explanation:
The triangles are similar because the angles are the same
We know nothing about the side lengths, so we can say nothing about concurrency. They may or may not be congruent.
Just set the equations equal to each other
(1,-4)
116100 will be 90% of the selling price
The will need to sell for 116100 / 90 x 100 = $129000