how would you solve this and what would the answer be? im very confused

Answer:
141 degrees.
Step-by-step explanation:
This is a seven sided polygon so first we work out the total value of the interior angles from the formula:
Total angles = 180(n - 2)
= 180 * (7-2)
= 180 * 5
= 900 degrees.
Therefore x = 900 - (122+125+148+107+126+131)
= 900 - 759
= 141 degrees.