We have been given that the standard deviation of a group of 20 scores is 15 and we are asked to find variance.
Since we know variance is square of standard deviation. In order to find out the variance of the given data we have to take the square of 15.
Therefore, our variance is 225.
For the first one it is 4n^2-4
Answer:
The amount driven would be 275, and the cost for both plans will be 77.75$
Step-by-step explanation:
make both equations
y=0.09x+53
y=0.13x+42
set them equal to each other and solve for x to get the distance
take that number and put it in one equation and solve for y to get the price of the plan for that value
The second-degree polynomial function f(x) that has a lead coefficient of 4 and roots 5 and 2 is f(x) = 4x² -28x + 40. The correct option is the last option f(x)=4x²-28x+40
<h3>Quadratic equation</h3>
From the question, we are to determine which second-degree polynomial function f(x) has a lead coefficient of 4 and roots 5 and 2
To determine this, we will use the given roots to determine the equation
The roots are 5 and 2
Thus
x = 5 and x = 2
x - 5 = 0 and x - 2 = 0
Therefore,
(x -5)(x -2) = 0
Distributing
x(x -2) -5(x -2) = 0
x² -2x -5x + 10 = 0
x² -7x + 10 = 0
Now, multiplying through by 4, we get
4x² -28x + 40 = 0
Thus, the function becomes f(x) = 4x² -28x + 40
Hence, the second-degree polynomial function f(x) that has a lead coefficient of 4 and roots 5 and 2 is f(x) = 4x² -28x + 40. The correct option is the last option f(x)=4x²-28x+40
Learn more on Quadratic Equation here: brainly.com/question/19257086
#SPJ1
Answer:
Like the angles BAC (56°) and BDC has the same arc BC in the circumference, these angles must be congruent, then angle BDC must be equal to 56°.
