Find the mean of the first four test scores first.
(Add all numbers in set and divide by how many numbers there are)
81 + 87 + 71 + 89 = 328 / 4 = 82
Then, find the mean with the 85 added as the fifth term.
81 + 87 + 71 + 89 + 85 = 413 / 5 = 82.6
The impact that the 85 had on the mean test score was that the mean/average increased by 0.6.
Answer:
ok i kow this hold on
Step-by-step explanation:
Answer:
1)· 5x + 2y = 9. First we solve for y. 2y= 9 -5x. y=(9-5x)/2. Now that we have the value of y. We substitute on the original equation and resolve. 5x + 2y = 95x + 2y = 9 5x + 2(9-5x)/2 = 9 5x + 9 - 5x = 9 9 = 9
That would be x = 1
Now substitute and resolve to find y.
5(1) + 2y = 9
5 + 2y = 9
2y = 4
y = 2
So our answer x=1 and y = 2. (1,2)
Proof :
5(1) + 2(2) = 9
5+ 4 = 9
9 = 9
Step-by-step explanation:
hoped it helped for the first one i didnt now the second one
I hope this helps you
a=4
b=9
c= -1
disctirminant =b^2-4ac
disctirminant =9^2-4.4. (-1)
disctirminant =97
x1=-9+square root of 97/2.4= -9+square root of 97/8
x2= -9-square root of 97/2.4= -9-square root of 97/8
Answer:
2 sqrt(5) =x
Step-by-step explanation:
We can use the Pythagorean theorem since this is a right triangle
a^2 + b^2 = c^2
2^2 +4^2 = x^2
4+16 = x^2
20 = x^2
Take the square root of each side
sqrt(20) = sqrt(x^2)
sqrt(4*5) = x
sqrt(4) sqrt(5) =x
2 sqrt(5) =x
