Answer:
Use the appropriate entry method for piecewise functions for the graphing calculator of interest.
Step-by-step explanation:
For Desmos, the entry looks like ...
f(x) = {x ≤ 2: -2x-1,-x+4}
_____
For a TI-84 calculator, the entry may look like ...
Y₁ = (-2X–1)(X≤2) + (-X+4)(X>2)
The symbols ≤ and > come from the TEST menu, which is the (2nd) shift of the MATH key.
Note that the function is the sum of the pieces, each piece multiplied by a test. For something like 0≤x<2, the multiplier would be a pair of tests:
... (0≤X)(X<2)
 
        
             
        
        
        
I that 'y' is 45 degrees because of alternate angles (I think its called).
If you look at the large triangle on the left where the corner angles are 35 and 80 and 20+an unknown angle. We can work out the missing angle by doing 180-80-35-20= 45. 
And so if we use the fact that alternate angle must be equal then y= 45 degrees (I think!)
        
                    
             
        
        
        
A=adult
c=children
total lumber=30
total number=adults+children
a+c=30
total cost=50
total cost=acost+ccost
acost=a times cost per adult=a times 3=3a
ccost=c times cost per child=c tiems 1=1c=c
total cost=3a+c
50=3a+c
equiaotn are
a+c=30
3a+c=50
multiplyu first by -1 and add
3a-a+c-c=50-30
2a=20
a=10
sub
10+c=30
c=20
answer is A
        
                    
             
        
        
        
What is the permiter problems first?? all you need to do to find perimeter is multiply the length by the width
        
             
        
        
        
<span>Wich fraction can be replaced with one half when estemating fraction
Example
</span>

<span>
</span>