20%of £800 is 800÷5 =160
800 + 160 =960
Answer:
54
Step-by-step explanation:
![\frac{4}{3} \pi r^{3} =12\pi \\r=\sqrt[3]{9} \\surface area 4\pi r^{2} = 4\pi (\sqrt[3]{9} )^2=54.372 (3dp)](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7B3%7D%20%5Cpi%20r%5E%7B3%7D%20%3D12%5Cpi%20%5C%5Cr%3D%5Csqrt%5B3%5D%7B9%7D%20%5C%5Csurface%20area%204%5Cpi%20r%5E%7B2%7D%20%3D%204%5Cpi%20%28%5Csqrt%5B3%5D%7B9%7D%20%29%5E2%3D54.372%20%283dp%29)
Answer:
See explanation
Step-by-step explanation:
16. Two parallel lines are cut by transversal. Angles with measures
and
are alternate exterior angles. By alternate exterior angles, the measures of alternate exterior angles are the same:

Then

17. Two parallel lines are cut by transversal. Angles with measures
and
are alternate interior angles. By alternate interior angles, the measures of alternate interior angles are the same:

Then

18. Two parallel lines are cut by transversal. Angles with measures
and
are alternate exterior angles. By alternate interior angles, the measures of alternate exterior angles are the same:

Then

19. The diagram shows two complementary angles with measures
and
. The measures of complementary angles add up to
then

Hence,

Check:

20. Angles
and
are vertical angles. By vertical angles theorem, vertical angles are congruent, so

Hence,

21.
and
are supplementary. The measures of supplementary angles add up to
so

Therefore,

Answer:
Step-by-step explanation:
9x - 4 + 5x + 16 = 180
14x + 12 = 180
14x = 168
x = 12