Answer:
15-29= -14
(I need the explanation most importantly)
14+(-4) - 8 =10-8=2
(Explanation please)
-8.4 - (19.5.) = - 27.9, (just add them to each other and write -, because both have - in front of them)
(Explanation)
-15 + 8 - (-19.7) = - 7+19,7=12,7 (there is + and - so it will became - 7, and at next there is two - which will turn them into +)
(Explanation)
29.45 - 56.009 - 78.2=−104,759 (all you have to is to put them all together, and than make it 29.45 less, writing - in front of them)
(Explanation)
LAST ONE
45.9 - (-9.2) + 5= 45.9+9.2+5=55.1+5=60.1 (because when there is 2 minus next to each other it will became plus)
Answer:

Step-by-step explanation:
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Isolate
for
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Substitute
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Isolate
for
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For

Substitute 



The solution to the system of equations are:

Hope I helped. If so, may I get brainliest and a thanks?
Thank you. Have a good day! =)
Hello.
To find the diameter you use this equation:
Radias<span>cm x 2/pie
</span>
So it would be 124=π*d
d=124/π
So the answer would be :
d=39.47=39.4 feet
Have a nice day