Answer:

Step-by-step explanation:

2x + y = 8
x - y = 10
--------------add
3x = 18
x = 6
x - y = 10
6 - y = 10
-y = 10 - 6
-y = 4
y = -4
solution is : (6,-4)
Rectangular form:
z = -2.1213203-2.1213203i
Angle notation (phasor):
z = 3 ∠ -135°
Polar form:
z = 3 × (cos (-135°) + i sin (-135°))
Exponential form:
z = 3 × ei (-0.75) = 3 × ei (-3π/4)
Polar coordinates:
r = |z| = 3 ... magnitude (modulus, absolute value)
θ = arg z = -2.3561945 rad = -135° = -0.75π = -3π/4 rad ... angle (argument or phase)
Cartesian coordinates:
Cartesian form of imaginary number: z = -2.1213203-2.1213203i
Real part: x = Re z = -2.121
Imaginary part: y = Im z = -2.12132034
Answer:
B
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
To obtain this form use the method of completing the square
Given
x² - 8x + y² - 2y - 8 = 0 ( add 8 to both sides )
x² - 8x + y² - 2y = 8
add ( half the coefficient of the x/y terms )² to both sides
x² + 2(- 4)x + 16 + y² + 2(- 1)y + 1 = 8 + 16 + 1
(x - 4)² + (y - 1)² = 25 → B
5m+2m+2 = 23
7m=21 , So:: m=21:7
m=3