Answer:
Step-by-step explanation:
hello :
an equation of this graph is : f(x) = a(x-h)²+k when (h,k) the vertex
so : h=5 and k= -4
f(x) = a(x-5)²-4....... now calculate : a
the y- intercept is : - 6.5 means : f(0) = - 6.5
put x=0 and f(x) = - 6.5
you have : -6.5 = a(0-5)²-4
-6.5 = 25a - 4
25a = -2.5 so : a= -2.5/25= 1/10
the equation is :
<h2>f(x) = (1/10)(x-5)²-4</h2>
Slope Formula: y2 - y1 / x2 - x1
(m and slope represent the same quantity)
m = 1 - - 5 / -4 - 0
m = 1 + 5 / -4
m = 6 / -4
m = -3/2
Now that we know the slope, we can plug the slope and one of our points into slope-intercept form (y = mx + b) and solve for b. I will be using the point (-4,1).
y = -3/2x + b
1 = -3/2(-4) + b
1 = 6 + b
b = -5
In point form, the y-intercept is (0, -5).
Therefore, to get the equation all we need to do is plug in our slope and b-value to slope-intercept form.
Equation: y = -3/2 x - 5
To check the point (-6, -14) we plug it into our equation and see if the two sides are equal.
-14 = -3/2(-6) - 5
-14 = 9 - 5
-14 = 4
-14 does not equal 4, therefore the point is NOT on the line.
Hope this helps!
Answer: 24 students
Explanation:
(20 + 23 + 25 + 28)/4
= 96/4
= 24
Therefore the mean is 24 students in the class.
Half of 45 is 22.5 or 22 1/2!