Answer: B
The graph of the proportional relationship equation is a straight line through the origin.
I hope this is good enough:
No picture so I can’t answer this .
Use quadratic formula
if you had ax^2+bx+c=0, then
x=

a=1
b=?
c=34
subsitute

=5+/-3i

=5+/-3i
make 5+/-3 into fraction over 2,(10+/-6i)/2

=(10+/-6i)/2
multiply both sides by 2

=10+/-6i
we conclude that -b=10
b=-10
ok so equaton is
x^2-10x+34
Answer:
Apply the sine theorem in triangle ABC:
sin C = AB/AC = 4/5
=> C = arcsin(4/5) = 53.13 deg
As shown in picture, AB//CD. Using the same side interior angles theorem:
=> angle BCD = angle ABC = 90 deg
=> angle ACD = 90 - angle ACB = 90 - C = 90 - 53.13 = 36.87 deg
Apply the cosine theorem in triangle ACD:
cos C = AC/CD
=> CD = AC/cos C = 5/cos(36.87) = 5/0.8 = 6.25
=> Option C is correct
Hope this helps!
:)