The solutions or roots so-called are really just the x-intercepts, and for a quadratic equation, the vertex is found right half-way between those x-intercepts.
we can get the intercepts by zeroing out "y" or f(x), so let's take a peek at one of those,

so, the x-intercepts or solutions are at 5 and -1, let's take a peek what's the halfway point.
-1----0----1----
2 ----3-----4------5
well then, now we know the vertex is at x = 2, but, what's the y-coordinate of it anyway?
y = (x - 5)(x + 1)
y = (2 - 5)(2 + 1)
y = (-3)(3)
y =
-9
Answer:
Step-by-step explanation:
Given the function f(m)=20-0.25m to represent the amount of money f(m) she has left after talking m minutes, the zero of the equation can be gotten by setting f(m) to 0
f(m)=20-0.25m
0 =20-0.25m
-20 = -0.25m
m = -20/-0.25
m = 80
Hence Trudy will have talked for 80minutes if she has no money left
Answer: 
Step-by-step explanation:
Given
For figure (i) both triangles are congruent


For figure (ii)
Two triangles WXZ and WZY are congruent

The answer of all of this is 18 because 18.1 months so if you do the math you get 18-7x+20^2
Answer:
Volume of cone = (1/3) * Volume of cylinder
Step-by-step explanation:
Use the formulas
Volume of cone = (1/3)* π r^2 *h
Volume of cylinder = π r^2 *h
Therefore
Volume of cone = (1/3) * Volume of cylinder