Answer:
I nk a ......................
1.A: 86 is equal to (86=) 45 % (which is 0.45) of a number n so 86=0.45n
2. C 4 is npercent of 26, so 4=n*26 where n is a number in percent, with the percent sign!
4 because triangle based pyramids have four faces
Convert to vertex form
or easier
for y=ax²+bx+c
the x value of the vertex is

and the y value is found by subsituting the x value in for x
so
y=1x²+4x+11
a=1
b=4
the x value of the vertex is

the y value is found by subsituting -2 for x
y=(-2)²+4(-2)+11
y=4-8+11
y=7
the vertex is (-2,7)
Answer:
Finding b:
57+b = 180 (linear pair)
b = 123
Finding c:
c = 123 (vertical angles are always congruent