Tn=-2n+19
Step-by-step explanation:
Well in south africa we use Tn
Tn=a+(n-1)d
a=is the first term in the sequence which is 17
d=is the the difference between the terms which is - 2
Tn=17+(n-1)(-2)
Tn=17-2n+2
Tn=-2n+19
The last choice, since they have the same number in their square roots.
1.When all the three cut outs of the angles A, B, C placed adjacent to each other at a point, then it forms a line forming a straight angle, i.e. 180°.
Flence, it is proved that the sum of the three angles of a triangle is 180°.
Therefore, ∠A + ∠B + ∠C =180
I'm guessing it is C because after you solve for n (you need to multiply the five over to isolate n), you get 20.