What was the key reason for RBI cancelling HCBL

Find the area between the lines 18x +12y = 108, 9x  + 6y  = 27, x - axis and y -axis. 

If in two linear equations ax + by = c and dx + ey = f and a/d = b/e = c/f  then, which of the following is true about the two equations?

The slope of the equation  24x+ 8y =56 is

If, x - y radic; 3 = 23 and radic; 3x + y = 35

Find the angle between both the lines when they intersect each other.

If x - √3 y = 8 Find the slope in angle?

Find the value of 'a' and 'b' which satisfy the following equations:

9a + 7b = 30

4a - 5b = 62

If (5√P - 7√Q) = 5, [1.5P = 4Q-(R/3)+9] and (√P/√Q) = 1.6, then find out the value of ‘R’.

I. p² – 5p + 6 = 0                  

II. 36q² = 81

For which value of m, there is no solution to the equation -

a – b = 5

ma – 4b = 1