Answer: x = 5
Step-by-step explanation:
The area of a rectangle is the length times the width. Since the dimensions are given as functions of x, youre going to have to use FOIL to combine them, then set that answer equal to the given value of 72.
l*w = (x+3)*(x+4) = x^2 + 7x +12 = 72
Subtract 72 on both sides. There is a reason why we'll do this instead of subtracting 12. The quadratic formula will help us to solve for x.
x^2 + 7x - 60 = 0
Apply the quadratic formula
We cant have a negative x value because that would result in negative dimensions and a negative area, which is impossible in this context. So you want to add the 17 instead of subtracting it.
x = 5 and x = -12
An alternate way is just factoring the trinomial to:
(x+12)(x-5) = 0
-(4 1/5)
5(4)+1 = 21
Thus the answer would be -21/5
step 1
<span>compute the average: add the values and divide by 6
Average =(44+ 46+40+34+29+41)/6=39
step 2
</span><span>Compute the deviations from the average
dev: (44-39)=5,
</span>dev: (46-39)=7
dev: (40-39)=1
dev: (34-39)=-5
dev: (29-39)=-10
dev: (41-39)=2
step 3
<span>Square the deviations and add
sum (dev^2): 5^2+7^2+1</span>^2+-5^2+-10^2+2^2
sum (dev^2): 25+49+1+25+100+4-----> 204
step 4
<span>Divide step #3 by the sample size=6
(typically you divide by sample size-1 to get the sample standard deviation,
but you are assuming the 6 values are the population,
so
no need to subtract 1, from the sample size.
This result is the variance
Variance =204/6=34
step 5
</span><span>Standard deviation = sqrt(variance)
standard deviation= </span>√<span>(34)------> 5.83
the answer is
5.83</span>
Answer:
3:1
Step-by-step explanation:
Answer:
1 3/5 miles/hr
Step-by-step explanation:
Let C be the speed of the current
Let D be the distance between Chan's house and the park
We know that Distance, D, is = Speed x Time
-----
Chan's speed going upstream is (8 - C)mph.
That gives us:
D = (8-C)(3 hr)
Chan's speed going downstream is (8+C)mph
So we have:
D = (8+C)(2 hr)
We know that the d is the same for these two equations, so:
(8-C)(3 hr) = (8+C)(2 hr)
24 - 3C = 16 + 2C
5C = 8
C = (8/5) or 1 3/5 mph
