Answer:
3x - 4 = -12
Step-by-step explanation:
I'm assuming you mean triangle angles?
If so, all angles add up to 180 so combine them and set them equal to 180.
51+82+5x+2=180
135+5x=180
5x=45
x=9
The square of a binomial expands as follows:

Expanding all the binomials, we have

Sum like terms:

Simplify terms appearing on both sides:

Move all terms involving k to the left and all numbers to the right:

Divide both sides by -20:

Answer:
since there are an even number of negatives, just ignore them and multiply normally. 2 x 2=4
4 x 2=8
8 x 2=16
The answer is 16
Answer:
x=5
Step-by-step explanation: