An operation * is defined on the set of real numbers by a * b = ab + 2(a + b + 1). find the identity element
In the diagram above, O is the center of the circle,
∠UOT = 70º and ∠RST = 100º. Calculate ∠RUO.
A sector of a circle has an area of 55 cm2. If the radius of the circle is 10 cm, calculate the angle of the sector
[π = 22/7]
