I'll solve 21, and you then should be able to solve the rest on your own!
Since ADC is 135, that means that that whole angle is 135 degrees. In addition, since angles ADB and BDC add up to ADC, we get ADB+BDC=ADC=135=11x+9+7x=18x+9. Subtracting 9 from both sides, we get 126=18x. Dividing both sides by 18, we get x=7. Plugging that into 11x+9=BDC, we get 11*7+9=77+9=86
Answer:

Step-by-step explanation:

now,

thus, (-3, 0)
Answer:
Answer is B ( 314.9 m2)
Step-by-step explanation:
A= H(B)/2
A= 25.6(24.6)/2
A= 314.88
Answer:
Step-by-step explanation:
1.put your percent over a 100 so
125%/100 then put 60 over x
2.then cross multiply 100x60=6000
3.then divide 6000 by 125 which is percent
4.your answer is-48
Answer:
D) 3/15
Step-by-step explanation:
(-2/5) - (-9/15) = (-6/15) - (-9/15) = (-6/15) + (9/15) = 3/15