Let x=height. then base is x+4. plug what we know into the formula for the area of a triangle
A=½bh
16=½*(x+4)*(x)
32=x²+4x
x²+4x-32=0
(x+8)(x-4)=0
so x can be-8 our 4. when we plug-8 in for x we get a negative height. since a triangle cannot have a negative side length we discard-8 and try 4. height=4 and base=8
Circumference = 2πr
So the circumference of the track is C = 2π .2 or .4π
3 times around the track is .4π x 3 or 1.2π - this is the answer but most teachers will want you to use 3.14 for pi.
so 1.2 x 3.14 = 3.768 km
Do you notice that I waited until the end to use the actual value of pi (3.14) in my calculations.
Keeping things in pi units until the very end saves time.
Answer:
Choice A) 
.
Step-by-step explanation:
What are the changes that would bring 
to 
?
- Translate to the left by
unit, and - Stretch vertically (by a factor greater than .)
. The choices of listed here are related to :
- Choice A)
; - Choice B)
; - Choice C)
; - Choice D)
.
The expression in the braces (for example 
as in ) is the independent variable.
To shift a function on a cartesian plane to the left by 
units, add to its independent variable. Think about how 
, which is to the left of , will yield the same function value.
Conversely, to shift a function on a cartesian plane to the right by units, subtract from its independent variable.
For example, 
is unit to the left of . Conversely, 
is unit to the right of . The new function is to the left of . Meaning that should should add to (rather than subtract from) the independent variable of . That rules out choice B) and D).
- Multiplying a function by a number that is greater than one will stretch its graph vertically.
- Multiplying a function by a number that is between zero and one will compress its graph vertically.
- Multiplying a function by a number that is between
and zero will flip its graph about the -axis. Doing so will also compress the graph vertically. - Multiplying a function by a number that is less than will flip its graph about the -axis. Doing so will also stretch the graph vertically.
The graph of is stretched vertically. However, similarly to the graph of this graph , the graph of increases as increases. In other words, the graph of isn't flipped about the -axis. should have been multiplied by a number that is greater than one. That rules out choice C) and D).
Overall, only choice A) meets the requirements.
Since the plot in the question also came with a couple of gridlines, see if the points 
's that are on the graph of fit into the expression 
.
