The x becomes negative because the negative sign at the start of the parenthesis distributes to everything inside parenthesis so x becomes -x and the double negative becomes +6 so that is why
90,400-7,100=83,300
83,300/12=6,941.66667
Monthly Salary Rounded: 6,941.67
8 it is this !!!!!!!!!!!!!!!!
2x+38=180
2x=142 (or x+x=142 from which 2x=142)
x=71
The unknown angles are each 71
You know this answer is logical as, since two sides are 21 it hints that we are looking at an equilateral triangle, which means two of its angles will be the same