Answer:
8.
Denote the equation : y = ax + b
Use the first 2 values of x and y in table:
3a + b = 21
5a + b = 35
Subtract the 2 equations:
=> 2a = 14 => a = 7 => b = 21 - 3 x 7 = 0
=> The solution is y = 7x
9.
Denote the equation : y = ax + b
Use the first 2 values of x and y in table:
5a + b = 17
10a + b = 22
Subtract the 2 equations:
=> 5a = 5 => a = 1 => b = 17 - 5 x 1 = 17 - 5 = 12
=> The solution is y = x + 12
Hope this helps!
:)
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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4x+2x^2+3x-2x+7
First, you would combine like terms. In this case, you would add 4x and 3x then subtract 2x.
2x^2+5x+7
5x^2-2x+3+4x-2x^2
Once again, you must combine like terms. Subtract 2x^2 from 5x^2, then subtract 2x from 4x.
3x^2+2x+3
There you go! Hope it helps
-Lacy
Answer:
Yes, he can.
Step-by-step explanation:
To find the sale, you need to times the sale percentage by the original price so
60 x 0.50 = 30
Then you subtract the original price by the sale price so
60 - 30 = 30
So the with the sale, the price is $30.
Now the tax
Do the same
30 x 0.045 = 1.35
Now instead of subtracting you add so
30 + 1.35 = $31.35
Yes, he can afford it.
