Cos18-Sin18=root2Sin27

Two angles of a quadrilateral when taken together make two right angle. Find the sum of other two angles 

is there any material is available to buy from your institute sir? 
material like the exact information given in teachoo app about tax,accs,excel,tally.
if material is available, then please tell me the price, and how can i order sir?

I don't know how to solve problems in the lesson quadrilaterals

Solve quadratic equation for x

 x square-4ax-b square +4a square =0

Is there any bank giving credit against GST receivable 

Invoice format for GST payment on RCM

Is there any credit against GST credit receivable????

A person pays  $975 through instalments each less than the former by $5. The first instalment is $100. In how many instalments will the amount be paid?