Answer: 1000 hot dogs and and 1600 sodas were sold.
Step-by-step explanation:
Let x be the number of hot dogs and y be the number of sodas.
Given : The concession stand at an ice hockey rink had receipts of $6200 from selling a total of 2600 sodas and hot dogs.
Each soda sold for $2 and each hot dog sold for $3 .
Then, we have the following system of two linear equations:-

Multiplying 2 on both sides of (1), we get

Now, Eliminate equation (3) from equation (2), we get

Put x=1000 in (1), we get

Hence, 1000 hot dogs and and 1600 sodas were sold.
Answer:
40 times greater
Step-by-step explanation:
So you need to come up with a perfect square that works for the x coefficients.
like.. (2x + 2)^2
(2x+2)(2x+2) = 4x^2 + 8x + 4
Compare this to the equation given. Our perfect square has +4 instead of +23. The difference is: 23 - 4 = 19
I'm going to assume the given equation equals zero..
So, If we add subtract 19 from both sides of the equation we get the perfect square.
4x^2 + 8x + 23 - 19 = 0 - 19
4x^2 + 8x + 4 = - 19
complete the square and move 19 over..
(2x+2)^2 + 19 = 0
factor the 2 out becomes 2^2 = 4
ANSWER: 4(x+1)^2 + 19 = 0
for a short cut, the standard equation
ax^2 + bx + c = 0 becomes a(x - h)^2 + k = 0
Where "a, b, c" are the same and ..
h = -b/(2a)
k = c - b^2/(4a)
Vertex = (h, k)
this will be a minimum point when "a" is positive upward facing parabola and a maximum point when "a" is negative downward facing parabola.
The rate of change is the slope of this line
m = (y2 - y1)/(x2 - x1) = (13 - 5)/(4 - 0) = 8/4 = 2
Written out, this would be (x / 7) - 10 < -6
solved, it would be x < 28