Question

Na figura, a medida x, em graus, pertence ao intervalo:
a) (0, 15).
b) (15, 20).
c) (20, 25).
d) (25, 30).

Answer 1

5x+y+z = 180
y+z= 180 - 5x

7x+y=180
8x+z=180
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15x+y+z=360

15x+180-5x=360
10x = 180
x= 180/10
x=18