Answer:
Null hypothesis is rejected. Standard deviation is > 8 miles per hour
Step-by-step explanation:
σ [Population standard deviation] = 8 , s [sample standard deviation] = s
n [no of items] = 8
H0 [Null] : σ = 8 ; H1 [Alternate - Right Tail] : σ > 8
χ2 = (n - 1) . s^2 / σ^2
= 49 x (10.5)^2 / 82 = 5402.25 / 64
χ2 = 84.410
df [degree of freedom] = n -1 = 50 - 1 = 49
P value (χ^2 49 > 84.410) = 0.00125
p = 0.0013
p < α ie 0.05
So, H0 is rejected
Hence we state that standard deviation is > 8 miles per hpur
Y = (-1/9).x + 4
The slope m of the line perpendicular to y = (-1/9).x + 4 is equal to 9:
(if the product of 2 slopes = - 1, then the 2 lines are perpendicular)
y = 9x + b, Since it passes by the point (-1,0) , then:
0= 9(-1) + b and b = 9
Final equation:
y = 9x+9
Answer:
3. 6
Step-by-step explanation:
X - y = 4 ( Equation 1 )
X + y =8 ( Equation 2 )
equation 1 + equation 2
; 2x = 12
x = 12÷2
x =6
hope it helps ☺️
D: k= 36 it is that one because it’s a big number
3a + 6b = 45
2a - 2b = -12....multiply by 3
----------------
3a + 6b = 45
6a - 6b = - 36 ...(result of multiplying by 3)
---------------add
9a = 9
a = 1
3a + 6b = 45
3(1) + 6b = 45
3 + 6b = 45
6b = 45 - 3
6b = 42
b = 7
solution is : (1,7)
