List of sides in order from shortest to longest 

x = 12

m∠A = 104º

m∠B = 32º

m∠C = 44º

shortest side = B

middle side = C

longest side = A

Step-by-step explanation:

Recall that all angles in a triangle add up to 180º. Also recall that the side opposite largest angle is the longest side, and vice versa for the side opposite the smallest angle.

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for

thats one

step-by-step explanation: