<span>2x^2 - 2x - 1 = 0 a = 2, b = -2, c = -1 b^2 - 4ac = (-2)^2 - 4(2)(-1) = 4 + 8 = 12
so the answer is 12
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This should be your answer
First recognize that the unit rate we're finding is gallons per hour, or

.
rate for Tank 1 = x gallons per hour = <em>a</em> gallons / <em>b</em> hours

rate for Tank 2 = y gallons per hour = <em>c</em> gallons / <em>d</em> hours
Answer:
146 whistles
Step-by-step explanation:
First, convert 122 feet to inches, by multiplying it by 12
122(12)
= 1464
Divide this by 10 to find how many whistles he can make
1464/10
= 146.4
Since we can only have a whole number of whistles, we have to round down to 146.
So, he can make 146 whistles