Answer:
B (2.5, 0)
Step-by-step explanation:
2x - y = 5 (multiply all by 4)
8x- 4y = 20
-8x - 4y = - 20
eliminate the 4y
8x- 4y = 20
-8x - 4y = - 20
-------------------- –
16x = 40
x = 40/16 = 2.5
now we substitute x with 2.5
2x - y = 5
2(2.5) - y = 5
y = 0
Answer:
489.5 + m = 756.80 (the amount elias has, added to marks is equal to the total
(756.8- 489.5 = 267.30 which is the amount mark has.)
m= 267.3
the last option is the correct option
Step-by-step explanation:
The percentage of the radioactive isotope left is 25.0000%.
<h3>What is the half life?</h3>
The half life of a radioactive isotope is the time that will elapse before only half of the number of original isotopes will remain.
Now;
We are told that;
Half life (t1/2) = 55 days
Time taken (t) = 115 days
Ratio of isotope remaining = N/No
Thus;
N/No = (1/2)^t/t1/2
N/No = (1/2)^115/55
N/No = (1/2)^2
N/No =1/4
Hence, the percentage = 1/4 * 100/1 = 25.0000%
Learn more about half life of an isotope:brainly.com/question/16387602
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Answer:
SU = 15
Step-by-step explanation:
Given that,
Point T is on line segment SU. So,
SU = ST + TU
Putting all the values, we get :
SU = 12 + 3
SU = 15
Hence, the length of SU is 15 units.
Answer:
9:30am
Step-by-step explanation:
Given data
Start time= 8:20am
Folding time= 25min
Time spent on Puzzle= 45min
Total time = 25+45= 70min= 1:10 min
Therefore the time she finishes is
8:20+ 1:10= 9:30 am
Hence she finished by 9:30am
