One way you could solve this is to just multiply the top and bottom out so that you get 9/81, reducing it by 9/9 to get 1/9 or option C.
Another way would be to do
since dividing numbers with exponents would be subtracting the bottom exponent from the top exponent, provided that the base number (in this case 3) is the same for both. For this method, you would get
, which is equal to 1/9 or .1 repeating, the same answer that you'd get with the first method.
Answer:
x^2 + 18x + 81
Step-by-step explanation:
(x+9) (x+9)
then distributive property
Answer:
The correct answer is B
Step-by-step explanation:
Kinda complicated to explain, if you need me to then comment and I'll do it
Answer:
<h2><u>
y = -2x</u></h2>
Step-by-step explanation:
If you notice very carefully then you will see that the line passes through the points :
( 1 , - 2 )
( - 1 , 2 )
Hence the value of x = 1 when the value of y = - 2 .
We know that - 2 × 1 = - 2
⇒ - 2 x = y
⇒ y = - 2x
Hence the first OPTION is correct .
Verification :
For points ( - 1 , 2 ) we can write :
y = - 2x
⇒ 2 = - 2 × - 1
⇒ 2 = 2
Hence the answer is verified .
Always try to use the converse of the graphical method .
( Nothing converse is there ... just saying the opposite steps of that method :P )
I mean in graphical method we plot points and then join , here identify the joined points and then make the equation .
The person and his shadow make a right triangle as well as the tree and it's shadow. they will be similar right triangles containing angles that are equal. I'm in similar triangles the angles are proportional so a ratio could be used to determine the shadow length. this ratio is:
25/5 = x/15
(Notice that both the height of the person and
the height of the tree height of the tree are on
the bottom because these would be similar
sides and the same for the shadows with both
on top. this could easily have been switched
with the shadows on bottom and heights on
top like:
5/25 = 15/x
however I noticed the 25/5 could easily be
reduced. this eliminated the need for cross
multiplication.)
The 25/5 can be reduced to 5:
5 = x/15
and then multiply both sides by 15 and you get:
x = 75
so the answer is 75 feet long.
this can be checked various ways. using trigonometry we have the opposite and adjacent sides so tangent could be used to find the angle between the shadow and the hypotenuse. this is:
tan (x) = opposite/adjacent
opposite = height
adjacent = shadow
so:
tan (x) = 5/25 for person
tan (x) = 15/75 for tree
these equations both reduce to:
tan (x) = 1/5
And of both equations are the same then the angLee are equal creating similar triangles and a correct answer
