When any lines are parallel that means they have the same slope so the slope of the red line would also have a slope of -3/7
Answer:
Step-by-step explanation:
Because the coordinates for x = 0 is (0,-2) so that's your y- intercept.
Then if you all you have to do is make sure that you have the correct slope.
So i just made a table on paper and started going up and seeing what slope i'd need to match the table on the screen.
Welp. I sure hope you like the Pythagorean theorem...
Top line:
One point is (-2,-2) while the other is (3,-3)
Thus the distance in between is sqrt((3-(-2))^2+(-3-(-2))^2)=sqrt(5^2+(-1)^2)=sqrt(26)
Most right line:
One point is (4,-6) while the other is (3,-3)
Thus the distance in between is sqrt((3-4)^2+(-3-(-6))^2)=sqrt((-1)^2+3^2)=sqrt(10)
Most bottom line:
One point is (1,-6) while the other is (4,-6)
Thus the distance in between is sqrt(4-1)^2+(-6-(-6))^2)=sqrt(3^2+0^2)=sqrt(9)=3
Most bottom left line:
One point is (1,-6) while the other is (-2,-4)
Thus the distance in between is sqrt((1-(-2))^2+(-6-(-4))^2)=sqrt(3^2+(-2)^2)=sqrt(13)
Lastly the most left line:
One point is (-2,-2) while the other is (-2,-4)
Thus the distance in between is sqrt((-2-(-2))^2+(-2-(-4))^2)=sqrt(0^2+(2)^2)=sqrt(4)=2
Thus to find the perimeter, we add up all the sides to get
sqrt(26)+sqrt(10)+3+sqrt(13)+2=16.8668 or B
Answer:
Mean = 78.2
Standard deviation = 5.8
Step-by-step explanation:
Mathematically z-score;
= (x-mean)/SD
From the question;
12% of test scores were above 85
Thus;
P( x > 85) = 12%
P(x > 85) = 0.12
Now let’s get the z-score that has a probability of 0.12
This can be obtained from the standard normal distribution table and it is = 1.175
Thus;
1.175 = (85 - mean)/SD
let’s call the mean a and the SD b
1.175 = (85-a)/b
1.175b = 85 - a
a = 85 - 1.175b ••••••••(i)
Secondly 8% of scores were below 70
Let’s find the z-score corresponding to this proportion;
We use the standard normal distribution table as usual;
P( x < 70) = 0.08
z-score = -1.405
Thus;
-1.405 =( 70-a)/b
-1.405b = 70-a
a = 70 + 1.405b ••••••(ii)
Equate the two a
70 + 1.405b = 85 - 1.175b
85 -70 = 1.405b + 1.175b
15 = 2.58b
b = 15/2.58
b = 5.81
a = 70 + 1.405b
a = 70 + 1.405(5.81)
a = 78.16
So mean = 78.2 and Standard deviation is 5.8
