You have to plug in the values into the equation.
Since a=6, all the a's in the equation would be replaced by 6 and same goes for the b.
^ means exponent btw
= -[2(6)^2 -6- (5(6)^2-3(3)) -4(6)^2 +2(3)]
Calculate/ simplify
= -[2(36)-6 - (5(36) -9)-4(36)+6]
Multiply all the things in parenthesis
= -[72-6-(171)-144+6]
Add/subtract
= -[-243]
Negative times negative becomes positive therefore, the answer becomes 243
The answer to this questing is 100, because (23 x 2) + (18 x 3) = 100
Dividing both sides by rt,

The correct answer is 48%
There are 10 even numbers from 1 to 21.
That makes the probability of an even number 10 out 21.
10 / 21 x 100 = 48%