Answer:
Hence the value for the mean is 80 and the standard deviation for the original sample is 8.
Step-by-step explanation:
Mean = 83-3 = 80.
Here the standard deviation didn't change = 8.
Add up all the numbers & divide by the number of numbers. That should give you the mean.
y = −2x + 1
4x + 2y = −1
Replace Y in the second equation with the value of Y in the first one.
4x + 2(-2x +1) = -1
Distributive Property:
4x + -4x + 2 = -1
Combine like terms:
2 = -1 which is not true, so there are no solutions.
Answer:
20 units²
Step-by-step explanation:
The x-intercepts are symmetrically located around the x-coordinate of the vertex, so are at
1.5 ± 5/2 = {-1, 4}
Using one of these we can find the unknown parameter "a" in the parabola's equation (in vertex form) ...
0 = a(4 -1.5)² +12.5
0 = 6.25a +12.5 . . . . . simplify
0 = a +2 . . . . . . . . . . . divide by 6.25
-2 = a
Then the standard-form equation of the parabola is ...
y = -2(x -1.5)² +12.5 = -2(x² -3x +2.25) +12.5
y = -2x² +6x +8
This tells us the y-intercept is 8. Then the relevant triangle has a base of 5 units and a height of 8. Its area is given by the formula ...
A = (1/2)bh = (1/2)(5)(8) = 20 . . . . units²
Notice the grid, the points are (-5, -2) and (4, -1), thus