Answer:
area ≈ 6.3 units²
Step-by-step explanation:
Calculate the area (A ) of the sector as
A = area of circle × fraction of circle
= πr² × 
= π × 4² × 
= 16π ×
← cancel 8 and 16 by 8, leaving
A = 2π ≈ 6.3 units² ( to 1 dec. place )
Analytically, it will be
-√(1+1²) = -√2
The calculator shows it to be -1.41421356237
_____
= -√2 to 12 significant digits.
(3, -2)
Step-by-step explanation:
y = -2x + 4
-x + 3y = -9
-x + 3 (-2x + 4) = -9
-x + -6x + 12 = -9
-7x = - 9 – 12
-7x = - 21
X = 3
We substitute x with 3 to evaluate y;
-3 + 3y = -9
3y = -6
y = -2
Elimination Method;
y = -2x + 4
-x + 3y = -9
We arrange the equations for substitution;
2x + y = 4
-x + 3y = -9
We multiply the first equation with 3 so we can substract one variable to zero;
3 (2x + y = 4)
= 6x + 3y = 12
Then we subtract the two;
6x + 3y = 12
-x + 3y = -9
7x = 21
x = 3
We evaluate y by substitution x with 3 in one of the equation;
-x + 3y = -9
-3 + 3y = -9
3y = -6
y = -2
The final answer expressed as a coordinate point is;
(3, -2)
Answer: 769.3
Step-by-step explanation:

C=2*3.14*122.5
245/2=122.5
C=769.3