Explanation
Answer:
The carpenter can build the triangular frame by cutting the 12 foot piece by 2foot
W = -6
You get the formula from (8, -10) and the slope.
In the problem -5+x=0, x=5
Remark
The trick to this question is realizing what you took 1/3 of. Did you take it of the 150000 or is it 1/3 of some total you have to find. I don't think you could come up with a third choice.
It turns out that the answer is 1/3 of a number you don't know.
Equation
(1/3) x = 150000 Multiply both sides by 3
3*(1/3) x = 150000 * 3
x = 150000 * 3
x = 450000
Conclusion
The amount the company makes is 450000 dollars / year.