Answer:
Equation of the axis of symmetry is: x = 3
Step-by-step explanation:
The equation
![y=2x^2-12x+21](https://tex.z-dn.net/?f=y%3D2x%5E2-12x%2B21)
is the equation of a parabola, of the form
whose vertex is located at the x-coordinate:
![x_{vertex}=\frac{-b}{2\,a}](https://tex.z-dn.net/?f=x_%7Bvertex%7D%3D%5Cfrac%7B-b%7D%7B2%5C%2Ca%7D)
Then, for our case the x position of the given parabola, is:
![x_{vertex}=\frac{-b}{2\,a} \\x_{vertex}=\frac{12}{2\,(2)} \\x_{vertex}=3](https://tex.z-dn.net/?f=x_%7Bvertex%7D%3D%5Cfrac%7B-b%7D%7B2%5C%2Ca%7D%20%5C%5Cx_%7Bvertex%7D%3D%5Cfrac%7B12%7D%7B2%5C%2C%282%29%7D%20%5C%5Cx_%7Bvertex%7D%3D3)
Then the equation of the axis of symmetry, which is a vertical line that goes through the vertex, would be given by:
x = 3
Answer:
24 A-(8+8)
Step-by-step explanation:
Answer:This is a linear equation.
y = mx+b
y is the total cost.
The slope m is the rate: that's 9 dollars per hour.
x is the number of hours.
b is the initial value: that's 16 dollars.
y = 9x+16
The problem states that the cost was 79 dollars.
Substitute that for y and solve for x.
79 = 9x+16
63 = 9x
x = 7 hour
Step-by-step explanation:
Answer:
111/20 = 5.55
Step-by-step explanation:
He used a total of 1 3/4 and 3 4/5 salt.
Convert both these mixed numbers into fractions.
=> 7/4 + 19/5
Take the LCM of the denominators
=> 35/20 + 76/20
Add the numerators
=> 111/20 = 5.55
He used a total of 111/20 or 5.55 kgs of salt.