Answer: #21. 44 degrees #23. 30 degrees
Step-by-step explanation: The full triangle equals 180 degrees that's a fact. In #21 we have to find the value of x. To do so we add up all the phrases in the triangle and make the equal to 180, then you get x+-7 and you substitute -7 for x to get 44 degrees as your answer.
For #23 we see a linear pair with the angle that equals 130 degrees so we know the blank angle to the left will equal 50 degrees. the angle that equals 8x+4 is a vertical angle to the angle above so that angle also equals 8x+4 and knowing all the measures of the triangles we can add up the degrees to equal 180 degrees as we did in #21. we get that x=12 and we substitute 12 in for x in the phrase 3x-6 to get that the angle equals 30
