Answer:
the rate of change of the area is Ra= 80 mm² per second
Step-by-step explanation:
the area of a rectangle (A) is
A = L * W , L= length and W= width
if the width remains constant the change in the area is only due to the change in length , thus:
ΔA = Δ( L * W ) = W * ΔL , where ΔA represents the change in area and ΔL represents the change in length
ΔA = W ΔL
denoting Δt as the time required to change, and dividing both sides by Δt
ΔA/Δt = W ΔL/Δt
where Ra=ΔA/Δt = rate of change of the area and RL=ΔL/Δt rate of change of the length.
thus
Ra = W * RL
replacing values
Ra = W * RL = 8 mm * 10 mm/second = 80 mm² /second
Answer:
1. Yes it does. It's a function because it pass in the vertical line test, which tell us that if you can draw an vertical line through the graph and this line touches the graph in only one point, it is a function.
2. B. I and II only
3. A. y = 8/7 x +5
12
--------------------------
Answer:
x^2-2x-15
Hope this helps!
Let's put this on the usual Cartesian grid just so we can talk about it without drawing a picture. We'll use map conventions, right is east, up is north.
The ball starts at (0,0). 10.3 feet northwest means we have an isosceles right triangle whose diagonal is 10.3 feet. It's isosceles because northwest means equal parts north and west.
The sides of these triangles are in ratio

so the coordinates after the first putt are

The negative sign indicates west, which doesn't really matter for this problem. The distance from the origin to this point is 10.3 as required.
Now a second putt of 3.8 feet north puts us at

The squared distance to the origin is exactly

A little calculator work tells us

Third choice.