I'll solve it algebraically
x+y=4
x-3y=12
multiply first equatoin by -1 and add to second
-x-y=-4
<u>x-3y=12 +</u>
0x-4y=8
-4y=8
divide both sides by -4
y=-2
sub back
x+y=4
x+-2=4
add 2 to both sides
x=6
x=6
y=-2
(6,-2)
Answer:
n is a positive integer and here 90, 91, 92, 93, 94 and 95 is 9⁰ = 1
9¹ = 9
9² = 81
9³ = 729
9⁴ = 6561
9⁵ = 59049
so mathematical induction is prove given below.
Step-by-step explanation:
9⁰ = 1
9¹ = 9
9² = 81
9³ = 729
9⁴ = 6561
9⁵ = 59049
lets us consider by P (n) for the base case n = 0 then 9⁰ = 1 So P (1) is true
k ≥ 1so consider all integers
1≤l≤ k
There is a need to prove P (k+1)
if k is odd
=
.9.
is 9 so
= 9 +10m
then
= 9 ( 9 + 10m)
=81 + 10 (9m)
so digit is 1 and k +1 is even
Answer:
Critical value: z = 1.28
The 80% confidence interval for the mean repair cost for the washers is between $46.487 and $82.033.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of 
So it is z with a pvalue of 1-0.1 = 0.9, so z = 1.28
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.
So

The lower end of the interval is the mean subtracted by M. So 64.26 - 17.773 = $46.487.
The upper end of the interval is M added to the mean. So 64.26 + 17.773 = $82.033.
The 80% confidence interval for the mean repair cost for the washers is between $46.487 and $82.033.
Answer: 308in^2
Explanation:
Area = 22 x 14
A = 308
Answer:
y=-1/5 x +7/5
Step-by-step explanation:
First lets find the slope of the line containing the points (2,3) and (1,-2) by using the equation for slopes m1 = (y2 - y1) / (x2 - x1),
Which results in m1=5
If two lines are perpendicular, then their slopes must satisfy the following condition
m1*m2=-1
So, our new line must have the following slope (m2): m2*m1=1, if m1=5, then m2=-1/5
The line passes through P(-3,2)
Remember that the equation for a line is given by the following:
y=mx+b
if we eval P inside that equation, with m=-1/5
we have b.
2=-1/5*-3 +b
b=2-3/5