I don’t know , why don’t you tell me why they were selected
<span>3x^2 + 4x + 8 + 2x^2 - 6x + 3 to give result as 9x^2 -2x - 5
</span>3x^2 + 4x + 8 + 2x^2 - 6x + 3
= 5x^2 - 2x + 11
so
9x^2 -2x - 5 - (5x^2 - 2x + 11)
= 9x^2 -2x - 5 - 5x^2 + 2x - 11
= 4x^2 -16
answer
expression (4x^2 -16) must be added to the sum of (3x^2 + 4x + 8) and (2x^2 - 6x + 3) to give the result as (9x^2 - 2x - 5)
Y=20+35x because the 20 is a 1 time thing and 35x because 35 is charged each month
Answer:
[Vertex form]
Step-by-step explanation:
Given function:

We need to find the vertex form which is.,

where
represents the co-ordinates of vertex.
We apply completing square method to do so.
We have

First of all we make sure that the leading co-efficient is =1.
In order to make the leading co-efficient is =1, we multiply each term with -3.


Isolating
and
terms on one side.
Subtracting both sides by 15.


In order to make the right side a perfect square trinomial, we will take half of the co-efficient of
term, square it and add it both sides side.
square of half of the co-efficient of
term = 
Adding 36 to both sides.


Since
is a perfect square of
, so, we can write as:

Subtracting 21 to both sides:


Dividing both sides by -3.

[Vertex form]
Answer:
4
Step-by-step explanation:
Multiply both sides by 7.
5s+8=28
Subtract 8 from both sides.
5s=20
Divide 5 from both sides,
s=4