Answer:
Surface area of the wood to be painted = (
+ r 
)
- 16
Step-by-step explanation:
Surface area of a cone is given as the sum of the surface area and the area of its base.
i.e Surface area = + Lr
where: L is the length of its slant height and r is the radius.
Applying the Pythagoras theorem,
L =
Thus,
Surface area = r (r + )
The given cylindrical hole has a radius of 4 cm and depth 2 cm.
The area of one of its circular surfaces =
= × 
= 16 
The surface area of the piece of wood to be painted = surface area of cone - area of cylindrical circular surface.
Surface area of the wood to be painted = r (r + ) - 16
Answer:
A y = x + 1
Step-by-step explanation:
The line starts at 1 on the y-axis so the u intercept will be 1
A rational number is any number that can be turned into a fraction....it can be negative or positive.
Therefore, -12/6 is a rational number
Answer:
centre = (-5, -4)
radius = 7.42
Step-by-step explanation:
The general form for center-radius is
(x - h)² + (y - k)²= r²
Center = (h, k)
Radius = r
Rearrange the equation.
(x² + 10x) + (y² + 8y) - 14 = 0
Add 14 on both sides.
(x² + 10x) + (y² + 8y) = 14
(10/2)² = 25
(8/2)² = 16
Add 25 and 16 to both sides.
(x² + 10x + 25) + (y² + 8y + 16) = 14 + 25 + 16
Factor left side of the equation.
(x+5)² + (x+4)² = 55
(55) = (7.416198)²
(x+5)² + (x+4)² = 7.42²
The radius is 7.42.
The centre is at (-5, -4).
(r,theta) represents polar coordinate .
And in (r,theta), there is neither any restriction on r nor on theta. It means both r and theta can either be positive or negative .
For e.g. (2,30 degree), (2,-30 degree) both are correct .
So the given statement is true .
