Question

Solve for x.



Enter your answer in the box.

x =
°

Answer 1

x = 109°

3*180° - 100° - 102° - 108° - 121° = 109°

Answer 2

Given any polygon with n sides, the sum of its interior angles is

$(n-2)\times 180^\circ$

Your polygon has 5 sides, so its interior angles sum up to

$(5-2)\times 180^\circ = 3\times 180^\circ = 540^\circ$

Which means that

$100+102+108+121+x = 540 \iff 431+x = 540 \iff x = 540 - 431 = 109$