Ineed with the following equation:

a^6 + a(4-b) + 6b

where a = -2

The first thing you want to do is put the -2 where the letter a is. then you would want to next multiply -2 six times. then multiply the -2 into 4 and also into b which will give you so far: -64 +8 +2b+6b. Then what you would want to do next is to add all the like terms. which in this case would be the -64 and 8 together and then the 2b and 6b together too. which then you should have : -56+8b=0 and then you would want to add the -56 to the other side which then would give you 8b = 56 and then you would divde each side by 8 and finally you would get b=7. ( I hope that was helpful for you)

the removal discontinuity of the following function at x=-6 or x=6.

Step-by-step explanation:

Since discontinuity are at x=0 ,6 or -6.

After cancelling, it leaves you with for x≠0.

Therefore, x+6=0(or x=-6) , x-6=0(or x=6)  is a removal discontinuity of the following function.