<u>Answer:</u>
○ 
<u>Explanation:</u>
<h3>What is a quadratic equation?</h3>
A quadratic equation is an algebraic equation where the highest power of
is 2. The general form of a quadratic equation is as follows:
,
where <em>a</em>, <em>b</em>, and <em>c</em> represent known constants, and
is the unknown.
In this question, if you take a look at the second option, you will see that it is possible to rearrange the equation to make it look the general form:

⇒ 
Therefore, this equation is quadratic.
The other three options are not quadratic equations because none of them have an
term in them.
Answer:
A(x) = x(200-x)
Step-by-step explanation:
400 feet of fencing to enclose a rectangular dog exercise pen means the perimeter of rectangle is 400 feet
If x is length and y is breadth. Perimeter is given by :
P = 2(x+y)
400 = 2(x+y)
⇒ (x+y) = 200 .....(1)
y = 200-x
Area of a rectangle is given by :
A = xy
A(x) = x(200-x)
Hence, the area as a function of length of rectangle is x(200-x).
Answer:
32
Step-by-step explanation:
77 quarters and dimes
q + d = 77
subtract q from both sides
d = 77 - q
---------------------------
A collection of quarters and dimes is worth $12.50 (1250 cents)
25q + 10d = 1250
substitute for d
25q + 10(77 - q) = 1250
distribute
25q + 770 - 10q = 1250
Combine like terms
15q + 770 = 1250
subtract 770 from both sides
15q = 480
divide both sides by 15
q = 32
Answer:
48,96
Step-by-step explanation:
As we saw it the numbers kept increasing by x2 (or times 2) so the next had to be the same.
peace
Answer:
The answer is 40
Step-by-step explanation:
55-15=40