1) Distribute 8(2x-14) + 13 = 4x - 27 then simplify like terms to get: 16x - 99 = 4x - 27.
2) Subtract 4x on both sides and at the same time add 99 to both sides to get: 12x=72.
3) Divide both sides by 12 to get x=6.
PART B: 6 makes the equation true because you just solved for it.
A=pR^2-2pr^2, since R=15 and r=7.5
A=225p-112.5p
A=112.5p
A≈353.25 ft^2
Let's assume they meant C=40 degrees. With an angle like that they're asking for approximation; we'll oblige.
The circumradius is the product of the triangle sides divided by four times the area.
Here we have remaining side given by the Law of Cosines.



The area is

The circumradius is
If b is in the first position then c can be in any 1 of the remaining 6 positions.
If we start with ab then the letter c can be in any one of 5 positions and if we have aab there are 4 possible positions for c and so on.
So the total number of possible sequences where b comes first = 6+5+4+3+2+1 = 21.
The same argument applies when c comes before b so that gives us 21 ways also.
So the answer is 2 *21 = 42 different sequences.
A more direct way of doing this is to use factorials:-
answer = 7! / 5! = 7 * 6 = 42.
( We divide by 5! because of the 5 a's.)