The range I think it should be [0,infinity)
~kites have adjacent sides equal~
x = 3x-12
move 3x to the other side as a negative number
-2x = -12
divide both sides by -2
-12 divided by -2 is 6
so, x is equal to 6
but, we aren't done yet because the questions asks for the value of angle b
substitute the value we found into the equation for angle b
3(6)-12
36-12
24
so, angle b has a value of 24 degrees
Answer:
19) 28°
20) 60°
21) 17°
Step-by-step explanation:
19)
Supplementary angles:
(x + 12)º + 140º = 180º
x + 12 + 140 = 180
x = 180 - 140 - 12
x = 28º
20)
Angles at a point:
(- 24 + x)° + 24° + 300° = 360°
- 24 + x + 24 + 300 = 360
x = 360 - 300
x = 60°
21)
Vertically opposite angles:
(1 + 3x)° = 52°
1 + 3x = 52
3x = 52 - 1
3x = 51
x = 17°
Answer: 1-20=2 and 60-80=4
Step-by-step explanation:
the first is 2 number of building
and the third one is 4 number of buldings
Hope this helps :)

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