2x - 3y = 3.....multiply by 4
5x - 4y = 4....multiply by -3
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8x - 12y = 12 (result of multiplying by 4)
-15x + 12y = -12 (result of multiplying by -3)
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- 7x = 0
x = 0 <===
Answer:
He needs to score a 19
Step-by-step explanation:
First, I found the mean of the three test scores. The mean was below 17 so I knew he needed a grade higher than the ones he already has. So I went up from 18. So my first equation was 15+18+16+19=68. then I divided by 4 which gives you a mean of 17. (Mean=average)
Answer:
13.3 hours
Step-by-step explanation:
% done by Nancy in 8 hours = 100% = 1
8 (% done by Nancy in 1 hour) = 1
% done by Nancy in 1 hour = 1/8
n = 1/8
Similarly,
% done by Nancy in 5 hours + % done by Carole in 5 hours = 1
5 (% done by Nancy in 1 hour + % done by Carole in 1 hour) = 1
n + c = 1/5
Since n = 1/8
% done by Carole in 1 hour = 3/40
Thus,
time taken by Carole to finish the job
Answer is D since one of the expressions isn't a polynomial
Answer:
$90,962.66
Step-by-step explanation:
The formula for this is, where V = amount after t years:
V = P(1 + r/n)^nt where P is the amount invested, r = the rate as a decimal fraction, n is the number of times interest compounded each year and t = the number of years.
Here, V = 340,000, r = 0.07, n = 4 , t = 19 and P is to be found.
340,000 = P(1 + 0.07/4)^(4*19)
340,000 = P( 1.0175)^76
P = 340,000 / (1.0175^76)
P = $90,962.66