All quadrilateral angles have to add up to a total of 360°, so we just need to add the angles we already have and subtract that from 360.
135+90+80=305
360-305=55 so your answer is 55!
Ln 26 = 3.2581 to the nearest ten thousandth
The commutative property of addition means the order of the addends doesn't matter; we get the same sum. In symbols

<span>11 + 7 = 7 + 11, choice B, is a good illustration of commutativity.
The next part asks us to use the commutative property. Looking at the choices, we see it's not the commutative property of addition we're to use, it's the commutative property of multiplication. Let's write that generally first:
</span>

Applying that, <span>(4 + 7) * 3 = 3*(4+7), again choice B.
</span>
Answer:
a
Step-by-step explanation: