-4(x+10)-6=-3(x-2)
-4x-40-6=-3x+6
-4x-46=-3x+6
-4x-46+46=-3x+6+46
-4x=-3x+52
-4x+3x=-3x+3x+52
-x=52
(-x/-1)=(52/-1)
x=-52
ANSWER

EXPLANATION
The given expression is

We regroup the numerical parts to get;

Now let us simplify the negative numbers.

We now subtract 19 from 42 to get;

We can't simplify further
Hence the simplest form is:

(n + 7)2 = n - 1
2n +14 = n - 1
2n - n +14 = n - n - 1
n + 14 -14 = -1 - 14
n = -15
(-15 + 7)2 = -15 - 1
(-8)2 = -16
-16 = -16
Angle BOC = 120
PROOF
Angle A + Angle B + Angle C = 180
So, Angle B + Angle C = 120 (Angle A = 60)
Now 1/2 (Angle B + Angle C) = 60
1/2 Angle B + 1/2 Angle C = 60..............i
In triangle BOC
1/2 Angle B + 1/2 Angle C + Angle BOC =180
(BO and CO are angle bisectors)
Or 60 + Angle BOC = 180 (using i)
OR ANGLE BOC = 120