Pentagons and hexagons can be irregular.
Anything that does not have congruent sides is irregular.
Hope that helped :))
A prediction that suggests what you expect will happened is called a Conjecture.
It is different from probability.
Answer:
D (I think)
Step-by-step explanation:
I used a right triangle calculator and that was the answer
Below is the process the calculator did, hope it helps.


Use the FOLD method<span>
(a+b)(c+d)=ac+ad+bc+bd
</span><span>−12<span>s<span><span>^2 </span><span></span></span></span>+ 3st + 8ts − 2<span>t<span><span>^2</span><span>
</span></span></span></span>Collect like terms
-12{s}^{2}+(3st+8st)-2{t}^{2}
Simplify
<span>-12{s}^{2}+11st-2{t}^{2}<span>−12<span>s<span><span>2</span><span></span></span></span>+11st−2<span>t<span><span>2
The answer is = -12s^2 + 11st - 2t^2</span></span></span></span></span>
Answer:


Step-by-step explanation:
Given


Solving (a): T7
Substitute 7 for n in 


Calculate S7 and S6



So:


Solving (b): Tn

Where 
Calculate
We have:

Open brackets



So:



Collect Like Terms

