Answer: y = -3(x + 
)² + 
, 
, 
<u>Step-by-step explanation:</u>
First, you need to complete the square:
y = -3x² - 5x + 1
<u> -1 </u> <u> -1 </u>
y - 1 = -3x² - 5x
y - 1 = -3(x² + 
y - 1 + -3(
) = -3(x² + + )
↑ ↓ ↑
= 
y - 1 - 
= -3(x + )²
y - 
- = -3(x + )²
y - = -3(x + )²
y = -3(x + )² +
Now, it is in the form of y = a(x - h)² + k <em>where (h, k) is the vertex</em>
Vertex = ,
Im pretty sure the answer is x=-2
Answer: Option <span>C. To get system B, the second equation in system A was replaced by the sum of that equation and the first equation multiplied by -3. The solution to system B will be the same as the solution to system A.
First equation of system A multiplied by -3:
(-3)(x+6y=5)
(-3)(x)+(-3)(6)=(-3)(5)
-3x-18=-15
Sum of the second equation of system A and the first equation multiplied by -3:
(-3x-18)+(3x-7y)=(-15)+(-35)
-3x-18+3x-7y=-15-35
-25y=-50
System B
x+6y=5
-25y=-50 </span>
I’m pretty sure he could only make 1 rectangle with 5cm because it’s an odd number which means he couldn’t stack them on top of each other evenly like he could with the 6cm rectangles, so he’d only be able to line them up next to each other and that’s it (I hope that’s right; sorry if it’s not but it makes sense to me lol)
Answer: x = 9
Step-by-step explanation:
15 / 20 = (2x + 3) / 28
cross multiply
15(28) = 20(2x + 3)
420 = 40x + 60
360 = 40x
x = 9
