For number 1. it is wrong. It is fresh water. Ocean water is salt water. I don't know the rest, sorry. I will come back if I find out though! :D
Answer:
x = a/(a² + b²) or x = -1/a
Step-by-step explanation:
a(a²+ b²)x² + b²x - a =0
Use the quadratic equation formula:

1. Evaluate the discriminant D
D = b² - 4ac = b⁴ - 4a(a² + b²)(-a) = b⁴ + 4a⁴ + 4a²b² = (b² + 2a²)²
2. Solve for x


Answer:12 5/8
Step-by-step explanation:
Add the whole numbers together. 3 + 9 = 12
Multiply 1/4 so that it will have the same dnominator as 3/8. 2(1/4)= 2/8
Add the fractions together. 2/8 + 3/8 = 5/8.
Add the whole number and fraction to get a mixed number. 12 + 5/8 = 12 5/8
5. Start by finding how many tiles make up the outer edge of the pool. We know that each tile is 3/4 foot, and that the entire length is 12 feet. So by doing a division, we'll find how many tiles there are:
12 ÷ 3/4 = 16. By looking at the picture, we can confirm this. By looking at the picture we also see that the pool is the same length as 14 tiles, so the fraction is 14/16 -> 7/8.