For the first part, the answer is choice B) 360. This applies to any polygon and it doesn't have to be an octagon. The sum of the exterior angles of any polygon is always 360 degrees. This is something you should memorize or have on a reference sheet.
For the second part, the answer is choice C) 142 degrees. We have a parallelogram (specifically a rhombus but that doesn't matter) so the adjacent angles are supplementary. This means they add to 180 degrees. Solving x+38 = 180 leads to x = 142
Best guess is it’s the second one but I believe it’s between A and B sorry If I’m wrong.
For
ax^2+bx+c=
and a=1
b/2 squared=c makes a perfect square
b=16
16/2=8
8^2=64
the value of c should be 64
factored form
(x+8)^2
4z+2(z-4)=3z+11 perform indicated multiplication on left side
4z+2z-8=3z+11 combine like terms on left side
6z/-8=3z+11 add 8 to both sides
6z=3z+19 subtract 3z from both sides
3z=19 divide both sides by 3
z=19/3
z=6 1/3
So there is only one solution when z=6 1/3