Answer:
$276
Step-by-step explanation:
Create a proportion where x is the cost to refinish the larger wood floor:
= 
Cross multiply and solve for x:
3x = 828
x = 276
So, to refinish the larger wood floor, it would cost $276
Answer:
x = -4
Step-by-step explanation:
2x² + 8x = x² - 16
x² + 8x + 16 = 0
x² + 4x + 4x + 16 = 0
x(x + 4) + 4(x + 4) = 0
(x + 4)² = 0
x = -4
1/12 is the square root of 1/144