Answer:
x = 23
Explanation:
The sum of two interior angles is equal to an exterior angle that is supplementary to the third interior angle.
We can write the following equation based on this information to find the value of x:
2x + 3 + 51 = 100 add like terms
2x + 54 = 100 subtract 54 from both sides
2x = 46 divide both sides by 2
x = 23