(ab + 4a - 6) - (ab - 6) = ab + 4a - 6 - ab + 6 = (ab - ab) + (6 - 6) + 4a = 4a
The gradient in the equation would be 1/4x
30:50
60:100
3:5
That's all I can think of right now...
Radicals cannot exist as a denominator, so you would multiply both Sqrt96 and Sqrt8 by the Sqrt8, giving you Sqrt768 over 8 (since a sqrt times itself is the base number, in this case 8) then you would simplify Sqrt768 into 16 x Sqrt3, leaving you with 16xSqrt3 over 8. simplify into 2Sqrt3 by dividing.
D. b-3 would be 1, which is not greater than or equal to 5