The answer is b.
The length of the rectangle is 3w-150.
The width is w.
To get area you multiply length and width so w(3w-150)=70,200. The numbers in parentheses is the length.
You use distributive property and distribute the w to get 3w^2-150w=70,200.
You can simplify the equation by dividing both sides by 3 to get w^2-50w=23,400.
Then you get all the numbers on the left side of the equation by subtracting 23,400 to get w^2-50w-23,400=0.
Now that the equation equals zero, you can factor it to get (w+130)(w-180)=0.
Then you find the values for x with each factor which are x=-130 or x=180.
We would use the positive value for x because it is area.
You substitute 180 for x in 3w-150 and you would get 390.
