Answer:
‼️A) 12‼️
Step-by-step explanation:
Key skills needed: Interior Angle Measure Theorem, Equation Creation
Step 1) First, we need to classify this shape. It has 7 sides, which means that we can use the Interior angle Theorem to find out the sum of all the interior angle measures
The theorem is: S = (n - 2)180S=(n−2)180
S is the sum of all interior angle measures
n is the number of sides of the polygon
Step 2) With this, we can plug in 7 for "n" (Since the figure has 7 sides) and get:
---> S = (7-2)180S=(7−2)180
---> (7-2) is 5 since 7 - 2 = 5 so --> S = 5(180)S=5(180)
---> 5(180) is the same as 5 x 180 which is 900 so --> S = 900S=900
This means that the sum of all interior angles is 900 degrees.
Step 3) Now, we have to find out the sum of all the angles that they gave us so:
---> 10x + 10x + 9 + 133 + 9x + 14 + 12x - 9 + 10x + 5 + 136 = 90010x+10x+9+133+9x+14+12x−9+10x+5+136=900
The left side is the sum of all interior angles in the shape, and the right side is what the sum should be when expressed as a number.
Step 4) We have to combine all like terms on the left side:
---> 10x + 10x + 9x + 12x + 10x = 51x10x+10x+9x+12x+10x=51x
---> 9 + 133 + 14 -9+5+136 = 2889+133+14−9+5+136=288
Step 5) This means that ---> 51x + 288 = 90051x+288=900
Subtract 288 from both sides and get:
---> 51x = 61251x=612 (900-288 = 612)
Then divide by 51 from both sides and get:
---> x = 12x=12 (612 ÷ 51 = 12)
Therefore A) 12 is your answer.
