For this, we will be using the quadratic formula, which is 
, with a=x^2 coefficient, b=x coefficient, and c = constant. Our equation will look like this: 
Firstly, solve the multiplications and the exponents: 
Next, do the addition: 
Next, your equation will be split into two: 
. Solve them separately, and your answer will be 
Answer:
I'm taking an educated guess here and saying that its option two.
I haven't done these problems in almost two years.
Capacity of the pool = 30 x 20 x 5 = 3000 ft³
Amount of water already filled = 30 x 20 x 4 = 2400 ft²
Amount of water needed to full the pool = 3000 - 2400 = 600 ft²
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Answer: 600 ft² of water is needed to fill up the pool.
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Number 4. will be a. because if you do 7*9=63*10=630.
Answer:
it should be 3.) x+2
Step-by-step explanation:
