Answer:
6n - 1.
Step-by-step explanation:
Arithmetic sequence.
a1 = 5, d = 6.
nth term = a1 + d(n - 1)
= 5 + 6(n - 1)
= 5 + 6n - 6
= 6n - 1.
We have that
the expression 2f + 4f + 2 – 3-------> we can group it (2f+4f)+(2-3)
(2f+4f)+(2-3)=(6f-1)
therefore
the expression [2f + 4f + 2 – 3] is equivalent to [6f-1]
if the expression [6f-1] for f=3 is 17
then
the expression [2f + 4f + 2 – 3] for f=3 is also 17
<span>let's check it
</span>[2*3 + 4*3 + 2 – 3]--------> [6+12+2-3]=[20-3]=17------> is ok
A. The point estimate of μ1 − μ2 is calculated using the value of x1 - x2, therefore:
μ1 − μ2 = x1 – x2 =
7.82 – 5.99
μ1 − μ2 = 1.83
B. The formula for
confidence interval is given as:
Confidence interval
= (x1 –x2) ± z σ
where z is a value
taken from the standard distribution tables at 99% confidence interval, z =
2.58
and σ is calculated
using the formula:
σ = sqrt [(σ1^2 /
n1) + (σ2^2 / n2)]
σ = sqrt [(2.35^2 /
18) + (3.17^2 / 15)]
σ = 0.988297
Going back to the
confidence interval:
Confidence interval
= 1.83 ± (2.58) (0.988297)
Confidence interval
= 1.83 ± 2.55
Confidence interval
= -0.72, 4.38
155 = 2x -15
170 = 2x
85 = x
She had 85 when she first started.
Answer:
x = 1
y= -2
Step-by-step explanation:
to solve this system of equation , simultaneously using the substitution method
we say let
7 x + y = 5 ............................................. equation 1
2x - y = 4 ................................................... equation 2
from equation 2
2x - y = 4 ................................................... equation 2
2x - 4 = y
y = 2x -4.......................................................... equation 3
put the value of the y = 2x -4 into equation 1
7 x + y = 5 ............................................. equation 1
7x + 2x - 4 = 5
9x-4 = 5
9x = 5 + 4
9x = 9
divide both sides by the coefficient of x which is 9
9x/9 = 9/9
x = 1
substitute the value of x = 1 into equation 3
y = 2x -4.......................................................... equation 3
y = 2(1) -4
y = 2 - 4
y = -2
to check if you are correct put the value of x and y into any of the equations and you will see that the left hand side will be equal to the right hand side.
2x - y = 4 ................................................... equation 2
2(1) -(-2) = 4
2 + 2 = 4
4=4................................... proved
