Which of these is not a capital city?

abuja

cairo

kinshasa

johannesburg

Johannesburg

Explanation: Abuja is the capital of Nigeria, Kinshasa the capital of DRC(Democratic Republic of the Congo), Cairo is the capital of Egypt. Johannesburg is South Africa’s biggest city but not capital, South Africa is one of the only countries in the world, that has more than 1 capital, South Africa’s capitals are Cape Town, Pretoria, & Bloemfontein.

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