Okay, first, given the equation, we need to find out what the radius of the circle is. Let us state the general equation of a circle:

Where

is the centre of the circle. In this case, we don't need to know the centre. Just the radius.
Let us start by converting the equation into standard for, which I typed above. Divide both sides by 81.

Great! We now know the radius of the circle. It is

because it is the bottom fraction. Now we know that the radius is 9.
So now lets input this into the area of circle formula:
Now we insert our radius.
You can convert that into a decimal if you wish.
Hope this helped!
~Cam943, Moderator
Answer:
The rectangles are not similar
Step-by-step explanation:
In order to check whether they are similar, we need to take the ratio of their similar sides and ensure they are equal to a constant k.
Hence;
AB/PL = AD/LM = k
32/26 = 18/12 = k
16/13 = 9/6 = k
Since the scale factor is not the same, hence the rectangles are not the same.
The horizontal line has an equation: y = a, where a is any real number.
We know, the line passes through the point (-8, -7) → x = -8, y = -7.
<h3>Answer: y = -7</h3>
Answer:
See Below
Step-by-step explanation:
1) 180 ft / 6 sec
To find a unit rate, you need to have a denominator of 1 and to to do that, you can divide the numerator and denominator by the same number, in this case: 6.
30 ft / 1 sec
2) 86 mi / 5 hr
Same as above^(except dividing by 5)
17.2 mi / 1 hr
3) 83 mi / 5 hr
Same as above^^
16.6 mi / 1 hr
We can rewrite this as: 16.6 mph
4) 93 mi / 5 hr
Same as above^^^
18.6 mi / 1 hr
5) 150 mi / 4 hr
Same as above^^^^
37.5 mi / 1 hr
We can rewrite this as: 37.5 mph
Consider the contrapositive of the statement you want to prove.
The contrapositive of the logical statement
<em>p</em> ⇒ <em>q</em>
is
¬<em>q</em> ⇒ ¬<em>p</em>
In this case, the contrapositive claims that
"If there are no scalars <em>α</em> and <em>β</em> such that <em>c</em> = <em>α</em><em>a</em> + <em>β</em><em>b</em>, then <em>a₁b₂</em> - <em>a₂b₁</em> = 0."
The first equation is captured by a system of linear equations,

or in matrix form,

If this system has no solution, then the coefficient matrix on the right side must be singular and its determinant would be

and this is what we wanted to prove. QED