[ Answer ]

[ Explanation ]
(-y
- 3y - 5) - (3y
- 7y + 4)
[Remove Parenthesis]
-y
- 3y - 5 - (-3y
- 7y + 4)
-(-3y
- 7y + 4): 3y
+ 7y - 4
-y
- 3y - 5 + 3y
+ 7y - 4
[Simplify] -y
- 3y - 5 + 3y
+ 7y - 4: 2y
+ 4y - 9
= 2y
+ 4y - 9
![\boxed{[ \ Eclipsed \ ]}](https://tex.z-dn.net/?f=%5Cboxed%7B%5B%20%5C%20Eclipsed%20%5C%20%5D%7D)
Remember that for a quadratic function of the form

we can find its vertex with formula:

where

is the x-coordinate of the vertex; then we will find the y-coordinate by replacing

in our original function.
From the question know that

and

, so lets replace those values in our vertex formula to find the x-coordinate of our vertex:



Now lets replace that value into our original function to find the y-coordinate of our vertex:



Finally, we have our vertex (6,-9)
Now to graph our function we are going to take advantage of its line of symmetry; if the vertex is (6,-9) the line of symmetry of the parabola is x=6, so if we chose the point (6,0), our second point will have coordinates (3,0) as you can see in the picture.
Answer:
answer is opption "A" hope it will help u
35kg - a mass of sugar syrup
30% of 35kg it's a mass of sugar
30% = 30 : 100 = 0.3
30% of 35kg = 0.3 · 35kg = 10.5kg - a mass of sugar
Add xkg water. Then we have (35 + x)kg of sugar syrup and still 10.5kg of sugar.
10.5kg is 25% of (35 + x)kg .
(35 + x) -- 100%
10.5 -- 25% <em>multiply both sides by 4</em>
42 -- 100%
Therefore we have the equation:
35 + x = 42 <em>subtract 35 from both sides</em>
x = 7
<h3>Answer: We should add 7kg of water.</h3>