The equation of a circle:

(h,k) - the coordinates of the centre
r - the radius
Answer:
Step-by-step explanation:
By using the Pythagorean theorem:
b^2+3^2=5^2
b^2+9=25
b=sqrt (25-9)
b=sqrt(16)
b=4
=> 4^2+7^2=c^2
16+49=c^2
65=c^2
=>c=sqrt(65)
c = (approximately) 8
Step-by-step explanation:
your teacher was very nice and warned you about the trap in the question.
so, really, what do we have to do ?
a full circle represents 360°.
the shaded sector is the full circle minus the white sector !
this is the same as directly calculating the shaded sector for 360-75 = 285°.
so, the area of a circle is
pi×r²
in our case
pi×20² = 400pi
the needed fraction of the whole circle is either
75/360, if we want to subtract it for the solution
or
285/360, if we want to calculate the solution directly.
both lead to the same result.
400pi×360/360 - 400pi×75/360 =
= 400pi × 285/360 = 10pi × 285/9 = 2850pi/9 =
= 316.6666666...pi ≈ 316.7pi
Dy/dx (2x⁵ y³ - 4y/x)
dy/dx (2y³ x⁵ - 4y/x)
dy/dx ( 2y³ x⁵ ) - dy/dx (4y/x)
= 2y³ 5x⁴ - (-4y × 1/x²)
=
10x⁶ y³ + 4y
-------------------
x²