The formula to find the surface area of a circle is: pi x radius², so if we square the radius the answer would be 25, then we multiply that by 3.14 and the answer would be around 78.5, so the answer is 78.5.
<u>Given</u>:
The given triangle is a right triangle.
The length of the hypotenuse is 31 units.
The length of the leg is 23 units.
One of the angle is x.
We need to determine the value of x.
<u>Value of x:</u>
The value of x can be determined using the trigonometric ratio.
Thus, we have;

Substituting
, the side opposite to the angle x measures 23 units and the hypotenuse is 31.
Thus, we have;

Dividing, we get;

Taking
on both sides of the equation, we get;


Rounding off to the nearest whole integer, we get;

Thus, the value of x is 48°
Hence, Option c is the correct answer.
Side a = 10.98991
Side b = 11.69522
Side c = 4
Angle ∠A = 70° = 1.22173 rad = 7/18π
Angle ∠B = 90° = 1.5708 rad = π/2
Angle ∠C = 20° = 0.34907 rad = π/9