Answer:
26 is the perimeter
Step-by-step explanation:
you add all of the side numbers just like this:
9+5+12= 26 :)
Hope this helped :D
Answer:
what do you need? ^-^ I can help you
we are supposed to explain
Which situation could be solved using the equation 
As we can see in the given equation , one number is -4 and the other number is 4
When we add two number of same value but opposite in sign we get zero.
This equivalent to the real life situation of paying a post paid bills.
Suppose you are using a post paid service , and the bills gets generated at the end of the month.
Suppose the bills amount is $x.
Once you pay that bills , then total outstanding again becomes $0.
Because 

Consider, LHS

We know,

We know,

So, using this identity, we get

can be rewritten as

<h2>Hence,</h2>


Answer:
X=20
Step-by-step explanation:
Sin(x+20)=cos(2x+10)
Sin(x+20)=sin(90-(2x+10)
X+20=90-2x-10
3x=60
X=20