If it's written correctly, I believe the points are (5 , 140) and (20 , 520). First equation indicates a parabola and the second a line. The parabola crosses the line at two points.
The equations we get are
l = 6 + 2w (We get this from "The length of the rectangle is 6 more than 2 times the width.")
and
2l + 2w = 140 (We get this from the perimeter. Two times the length plus two times the width equals the perimeter of a quadrilateral.)
The first equation can be written as
l - 2w = 6
So now we have
2l + 2w = 140
l - 2w = 6
____________
Add the two equations.
We get 3l = 146
Divide by 3 on both sides.
l =
48
Your answer is
48
.
Apply the Pyth. Theorem:
c^2 = 3^2 + 7^2, or c^2 = 9 + 49 = 58. Thus, c = sqrt(58).
To get 4 or fewer correct, at least 2 answers have to be wrong. And the probability of that is:
3/4 x 3/4=9/16
1-9/16=probability that 4 or fewer are correct=7/16 ☺☺☺☺
Binomial distribution formula: P(x) = (n k) p^k * (1 - p)^n - k
a) Probability that four parts are defective = 0.01374
P(4 defective) = (25 4) (0.04)^4 * (0.96)^21
P(4 defective) = 0.01374
b) Probability that at least one part is defective = 0.6396
Find the probability that 0 parts are defective and subtract that probability from 1.
P(0 defective) = (25 0) (0.04)^0 * (0.96)^25
P(0 defective) = 0.3604
1 - 0.3604 = 0.6396
c) Probability that 25 parts are defective = approximately 0
P(25 defective) = (25 25) (0.04)^25 * (0.96)^0
P(25 defective) = approximately 0
d) Probability that at most 1 part is defective = 0.7358
Find the probability that 0 and 1 parts are defective and add them together.
P(0 defective) = 0.3604 (from above)
P(1 defective) = (25 1) (0.04)^1 * (0.96)^24
P(1 defective) = 0.3754
P(at most 1 defective) = 0.3604 + 0.3754 = 0.7358
e) Mean = 1 | Standard Deviation = 0.9798
mean = n * p
mean = 25 * 0.04 = 1
stdev = 
stdev =
= 0.9798
Hope this helps!! :)