(-4b - 8) = 20
-4b = 20 + 8
-4b = 28
b = -7
Answer:
- minimum: 6.75 km²
- maximum: 13.75 km²
Step-by-step explanation:
Such questions generally arise in the context of measurement precision and/or accuracy. Apparently, we're to assume that these dimensions could be arrived at by rounding to the nearest km. In that case, they can be taken to have a possible error of ±0.5 km.
The minimum possible area is the product of the minimum possible dimensions: 1.5 km by 4.5 km = 6.75 km².
The maximum possible area is the product of the maximum possible dimensions: 2.5 km by 5.5 km = 13.75 km².
_____
<em>Comment on combining measurement values</em>
You will note that the nominal area is 2 km by 5 km = 10 km², and that the middle value between the minimum and maximum is slightly more than this, at 10.25 km².
It is typically the case that when measurements are combined by operations other than addition and subtraction, the nominal result is different from the middle result in the range of possibilities.
Each time its rolled it has a 1/6 chance of rolling a two. Out of 50, it should come up as 2 about 8.33 percent of the time. That is the theoretical probability. However, it came up as two 10 of the 50 times, or 20 percent. The difference is about 11.67
(8r + 6)(4r + 10) = 32r^2 + 80r + 24r + 60 = 32r^2 + 104r + 60