Answer:
w = .5
Step-by-step explanation:
-4w + 18w+2=10 -6w
14w + 2 -2 = 10 -2 -6w
14w + 2w = 8 - 2w + 2w
16w = 8
16w/16 = 8/16
w = .5
Answer:
28π cm²
Step-by-step explanation:
The surface of a cylinder is given by the formula:
where r is the radius of the base, and h is the height.
Using the image, we can find that the radius of the cylinder would be 2 cm, and the height would be 5 cm.
Now, to find the surface area of the cylinder, we would have to plug in 2 for r (the radius of the base) and 5 for h (the height of the cylinder) into the formula for the surface area of a cylinder.
Now we plug in 2 for r and 5 for h for the equation for the surface area of a cylinder:
2π(2)(5) + 2π(2)² = 20π + 2π(4) = 20π + 8π = 28π
Remember, the radius and the height are given to us in cm, and w are solving for surface area, so the answer should be in cm² (square centimeters).
The surface area of the cylinder would be 28π cm².
28π cm² would be an exact answer. For the approximate answer, plug in 3.14 (most math classes use 3.14 to approximate π) for π.
I hope you find this helpful. :)
Answer:
1. 14 = 2 + 12
2. 16 = 4 + 12
3. 18 = 6 + 12
4. 20 = 8 + 12
Step-by-step explanation:
Super easy. All you do is replace the numbers in your table with the corresponding letter. In this case we have a table of s and f.
Example for row two: f = s + 12. Replace s with 4 ( 4 is from your s column so you would replace it with that) then solve and plug in your answer (When you solve your answer, it will go under f column).16 = 4 + 12 . f = 16, s = 4.
Formula = f = s + 12.
1. 14 = 2 + 12
2. 16 = 4 + 12
3. 18 = 6 + 12
4. 20 = 8 + 12
Answer:
x ≈ 1.32, x ≈ - 5.32
Step-by-step explanation:
Given
x² + 4x - 7 = 0 ( add 7 to both sides )
x² + 4x = 7
To complete the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 7 + 4
(x + 2)² = 11 ( take the square root of both sides )
x + 2 = ± 
( subtract 2 from both sides )
x = - 2 ± 
Thus
x = - 2 - ≈ - 5.32 ( to 2 dec. places )
x = - 2 + ≈ 1.32 ( to 2 dec. places )
Answer:
Check the explanation
Step-by-step explanation:
Let X denotes steel ball and Y denotes diamond
= 1/9( 50+57+......+51+53)
=530/9
=58.89
= 1/9( 52+ 56+....+ 51+ 56)
=543/9
=60.33
difference = d =(60.33- 58.89)
=1.44
s12 = 1/9( 502+572+......+512+532) -9/8 (58.89)2
=31686/8 - 9/8( 3468.03)
=3960.75 - 3901.53
=59.22
s1 = 7.69
s22 = 1/9( 522+ 562+....+ 512+ 562) -9/8 (60.33)2
=33295/8 - 9/8 (3640.11)
=4161.875 - 4095.12
=66.75
s2 =8.17
sample standard deviation for difference is
s=![\sqrt{[(n1-1)s_1^2+ (n2-1)s_2^2]/(n1+n2-2)}](https://tex.z-dn.net/?f=%5Csqrt%7B%5B%28n1-1%29s_1%5E2%2B%20%28n2-1%29s_2%5E2%5D%2F%28n1%2Bn2-2%29%7D)
= ![\sqrt{[(9-1)*59.22+ (9-1)*66.75]/(9+9-2)}](https://tex.z-dn.net/?f=%5Csqrt%7B%5B%289-1%29%2A59.22%2B%20%289-1%29%2A66.75%5D%2F%289%2B9-2%29%7D)
= 
=7.93
sd = 
=
=7.93* 0.47
=3.74
For 95% confidence level 
=1.96
confidence interval is
=(1.44 - 1.96* 3.75 , 1.44+1.96* 3.75)
=(1.44 - 7.35 , 1.44 + 7.35)
=(-2.31, 8.79)
There is sufficient evidence to conclude that the two indenters produce different hardness readings.
