39. FALSE
40. Where is the answer?
For any circle with Cartesian equation
,
we have that the centre of the circle is
, and the radius of the circle is
.
So in the case that
,
we essentially have that
.
So the centre of the circle is
, and the radius is
.
Answer
0 is the answer
Step-by-step explanation:
Part (a)
The radius is r = 42 because OA = 42.
The circumference, aka distance around the circle, is
C = 2*pi*r
C = 2*(22/7)*42
C = 264
We're told that arc AB is 110 mm which is 110/264 = 5/12 of the full distance around the circle.
So we'll apply 5/12 to the full rotation 360 to get (5/12)*360 = 150
<h3>
Answer: 150 degrees</h3>
==============================================================
Part (b)
Compute the area of the full circle
A = pi*r^2
A = (22/7)*(42)^2
A = 5544
Then take 5/12 of this because we only want 5/12 of the full circle area (to get the area of the shaded pizza slice)
(5/12)*(5544) = 2310
<h3>Answer: 2310 square mm</h3>
==============================================================
Side note: Both answers are approximate because pi = 22/7 is approximate.
