Prove that the angle inscribed in a semi-circle is a right angle.
1 Answer
Given: O is the center of the circle, AB is diameter and ACB is an angle inscribed in a semi-circle.
To prove: ACB = 90°
S.N | Statements | Reasons |
1 | ACB = 1/2 AOB | ACB is a circumference angle and AOB is a central angle standing on the same arc as ADB. |
2 | AOB = 180° | A straight angle. |
3 | ACB = (1/2)*180 = 90° | From statements (1) and (2), by substitution axiom |
4 | Therefore, ACB is a right angle. | From statement 3. |
Topics from Math
Algebraic Equation
0
Algebraic Fraction
2
Circle
16
Construction
3
Statistics
12
Triangle and Quadrilateral
17
Trigonometry
12
Compound Interest
6
Cylinder and Sphere
3
HCF and LCM
9
Indices
5
Prism and Pyramid
5
Radical and Surd
0
Plane Surface
5
Compound Depreciation
3
Population Growth
1
Set
4
Tax and Money Exchange
0
Related Questions