Answer:
r=1/π
Step-by-step explanation:
Area of the circle is defined as:
Area = πr²
Derivating both sides
=2πr
=
x
= 2πr
If area of an expanding circle is increasing twice as fast as its radius in linear units. then we have : =2
Therefore,
2πr = 2
r=1/π
Answer:
y = -2x + 4
Step-by-step explanation:
First find slope:
We know equation of a line is y = mx + b, where m = slope and b = y-intercept, so we can plug in the slope:
y = -2x + b
The y-intercept of the equation is 4 because the coordinate (0, 4) is given. Therefore, the equation is:
y = -2x + 4