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:

Step-by-step explanation:

If two events are dependent on each other you have to multiply the probability of the first event times the probability of the second event.
first count all the marbles here there are 21
you are asked about picking two green marbles there are 7 out of the 21 total.
The first event would be 7/21
The second event would be 6/20 (since you didn't replace and you took out a green one)
now multiply your two fractions together:
and you get 1/10.
Step-by-step explanation:
3a-3(a+2)=10
3a-3a-6=10
+3 +3
6a-6=10
+6 +6
6a=16
Step-by-step explanation:
If it cost $1200 to install 100 square feet of roofing, then it will cost $13200 to have 1100 square feet installed.
$1200/ 100 square feet multiply 11 on both sides
$13200/ 1100 square feet
<h3><u><em>
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: )</em></u></h3><h3><u><em>
And as always, </em></u></h3><h3><u><em>
simplify bananas</em></u></h3>