You did a simple mistake by forgetting to add 4 to itself in the square root. (-4^2=16)
x=(4 +/- sqrt(16-8))/4
x=(4 +/- sqrt(8))/4
Is this enough to get you started again?
Black queen 2/52 and greater than 4 on a cube 2/6
3/4=.75
7.5/.75= 10
3.45*10=34.5
answer is $34.5
6% of $22 = 1.32
22 + 1.32 = 23.32 (cost of meal with tax)
20% of 23.32 = 4.66
23.32 + 4.66 = 27.98
Total cost = $27.98