Find the measure of angle A

This is an isosceles triangle, meaning it has 2 congruent angles and one other angle.

Looking at this triangle, we know that ∠B = ∠C.

∠B = 57 degrees

All the angles in a triangle add up to 180, so you need to subtract the two values from 180 to get ∠A.

∠A = 180 - 57 - 57

       = 66 degrees

Hope this helps!

∞ this is your sign

you can first factor out the n to get n(1+5). we know that 1+5 is 6, so we just have 6n.