Which statement about a unitary system of government is accurate? a. Key powers are held by the national government.
b. Power is shared equally between the people and the government.
C. The national government is made up of many small, self-governing states.
d. The government allows the people to make most political decisions.

a and b because with the other three, they simplify to something else.

the answer would be the third option, "no, ariel should have added 9^2 and 12^2 and compared that to 15^2."

this is found through the pythagorean theorem, which is a^2 + b^2 = c^2.

this is the correct way of solving the problem:

9^2 + 12^2 = 15^2

81 + 144 = 225

225 = 225