Let's use a formula in order to find how much the interior angles are supposed to add up to.
(n-2)×180; n is the number of angles.
(5-2)×180= 3×180=540
We need for the interior angles to add up to 540. Let's make an equation.
100+102+108+121+x=540
431+x=540; let's find x.
540-431= 109
So, X= 109°
Answer:
a. 1 1/8 b. 8/9
Step-by-step explanation:
You can set this up as a proportion to solve. For part a. we know that 2/3 of the road is 3/4 mile long. 2/3 + 1/3 = the whole road, so we need how many miles of the road is 1/3 its length. Set up the proportion like this:

Cross multiplying gives you:

The 3's on the right cancel out nicely, leaving you with

To solve for x, multiply both sides by 3/2:
gives you

That means that the road is still missing 3/8 of a mile til it's finished. The length of the road is found by adding the 3/4 to the 3/8:

So the road is a total of 1 1/8 miles long.
For b. we need to find out how much of 1 1/8 is 1 mile:
1 mile = x * 9/8 and
x = 8/9. When 1 mile of the road is completed, that is 8/9 of the total length of the road completed.
Answer:
86°
Step-by-step explanation:
180° is the sum of all angles in a triangle
The two angles given are 68° and 26°
The equation is : 180° - 68° - 26° = x°
180° - 68° - 26° = 86°
x° = 86°
If my answer is incorrect, pls correct me!
If you like my answer and explanation, mark me as brainliest!
-Chetan K