It will be a negative.
for an example: -20 for x would mqke 2x + 1 into -39 and 8x + 5 into -155. that's 116 apart, so maybe -2(8) + 5 = -11
-2(2) + 1 = -3
but that's only 8 apart, so it'd be higher.
-4(2) + 1 = -7
-4(8) + 5 = -27
BOOM
Tadaaaa,
You probably thought positive, but sometimes it's negative, you know what I mean?
You are not giving enough information but in one of the calsses the average of student's height might be greater than the other class beacause one of the two classes needs to have 1 extra person than the other calss
We need to account for both x values on either side of the length, and width.
Thus, the length becomes 10 + x + x = 10 + 2x
and the width becomes 5 + x + x = 5 + 2x
For the second question, I'm assuming we don't account for the area that is covered by the garden.
Then we can say that the path is measured by: (5 + 2x)(10 + 2x) - 50, which is the area of the garden itself.
(5 + 2x)(10 + 2x) - 50 = 54
Expanding the brackets:






x = -9, or x = 3/2
Since x > 0, then x ≠ -9
Thus, the only x-value we can take is x = 3/2
PV = P(1 - (1 + r)^-n) / r; where P is the periodic withdrawal = $100,000; r = rate = 5% = 0.05; n = number of periods = 20 years.
PV = 100000(1 - (1 + 0.05)^-20) / 0.05 = 100000(1 - 1.05^-20) / 0.05 = 100000(1 - 0.3769) / 0.05 = 100000(0.6231) / 0.05 = 100000(12.4622) = 1,246,221 ≈ $1,250,000