Respuesta :

Answer:

8. X = 10.5 and 19. X = 5

Step-by-step explanation:

8. You know that a triangle interior angles should add up to 180° so:

(10x - 11) + (3x - 2) + (3x + 1) = 180

180 = 16x - 12

168 = 16x

The you divide each side by 16:

168 ÷ 16 = 16x ÷ 16

X = 10.5

10. You know that a straight line equals 180° and interior angles add up to 180° so:

1st you do 180 - 151 = 29°

2nd (11x - 1) + (20x - 3) + (29) = 180

180 = 31x + 25

155 = 31x

The you divide each side by 31:

155 ÷ 31 = 31x ÷ 31

X = 5