Answer:
141°
Explanation:
In order to find the missing angle, we must first find the total sum of all the interior angles. To find this we use the following equation:
(n – 2) × 180°
Where n is equal to the number of sides
There are 7 sides therefore:
(7 – 2) × 180°
5 × 180°
900°
The sum of the total angles in the heptagon is 900°
We then must subtract all of the known angles
900 - 148 = 752
752 - 90 = 662
662 - 142 = 520
520 - 130 = 390
390 - 129 = 261
261 - 120 = 141
The missing angle is 141°