Angle between a chord and a tangent when angle in the alternate segment is given

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Given a circle whose chord and tangent meet at a particular point. The angle in the alternate segment is given. The task here is to find the angle between the chord and the tangent.
Examples:

Input: z = 48
Output: 48 degrees

Input: z = 64
Output: 64 degrees

Approach:

Let, angle BAC is the given angle in the alternate segment.
let, the angle between the chord and circle = angle CBY = z
as line drawn from center on the tangent is perpendicular,
so, angle OBC = 90-z
as, OB = OC = radius of the circle
so, angle OCB = 90-z
now, in triangle OBC,
angle OBC + angle OCB + angle BOC = 180
angle BOC = 180 – (90-z) – (90-z)
angle BOC = 2z
as angle at the circumference of a circle is half the angle at the centre subtended by the same arc,
so, angle BAC = z
hence, angle BAC = angle CBY

$\text{[math]}$
Below is the implementation of the above approach:

C++

// C++ program to find the angle
// between a chord and a tangent
// when angle in the alternate segment is given
 
#include <bits/stdc++.h>
using namespace std;
 
void anglechordtang(int z)
{
    cout << "The angle between tangent"
         << " and the chord is "
         << z << " degrees" << endl;
}
 
// Driver code
int main()
{
    int z = 48;
    anglechordtang(z);
    return 0;
}

Java

// Java program to find the angle
// between a chord and a tangent
// when angle in the alternate segment is given
import java.io.*;
 
class GFG 
{
 
    static void anglechordtang(int z)
    {
        System.out.print( "The angle between tangent"
            + " and the chord is "
            + z + " degrees");
    }
     
    // Driver code
    public static void main (String[] args) 
    {
        int z = 48;
        anglechordtang(z);
    }
}
 
// This code is contributed by anuj_67..

Python3

# Python3 program to find the angle
# between a chord and a tangent
# when angle in the alternate segment is given
def anglechordtang(z):
 
    print("The angle between tangent", 
          "and the chord is", z , "degrees");
 
# Driver code
z = 48;
anglechordtang(z);
 
# This code is contributed
# by Princi Singh

C#

// C# program to find the angle
// between a chord and a tangent
// when angle in the alternate segment is given
using System;
 
class GFG 
{
 
    static void anglechordtang(int z)
    {
        Console.WriteLine( "The angle between tangent"
            + " and the chord is "
            + z + " degrees");
    }
     
    // Driver code
    public static void Main () 
    {
        int z = 48;
        anglechordtang(z);
    }
}
 
// This code is contributed by anuj_67..

Javascript

<script>
// javascript program to find the angle
// between a chord and a tangent
// when angle in the alternate segment is given
 
function anglechordtang(z)
{
document.write( "The angle between tangent"
               + " and the chord is "
               + z + " degrees");
}
 
// Driver code
 
var z = 48;
anglechordtang(z);
 
// This code is contributed by Amit Katiyar 
 
</script>

Output:

The angle between tangent and the chord is 48 degrees

Time Complexity: O(1)

Auxiliary Space: O(1)

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