The fish population in a certain part of the ocean (in thousands of fish) as a function of the water's temperature (in degrees Celsius) is modeled by:p(x)=−2x2+40x−72Which temperatures will result in no fish (i.e. 0 population)?Enter the lower temperature first.Lower temperature: □ degrees CelsiusHigher temperature: □ degrees Celsius
Q. The fish population in a certain part of the ocean (in thousands of fish) as a function of the water's temperature (in degrees Celsius) is modeled by:p(x)=−2x2+40x−72Which temperatures will result in no fish (i.e. 0 population)?Enter the lower temperature first.Lower temperature: □ degrees CelsiusHigher temperature: □ degrees Celsius
Given quadratic function: We are given the quadratic function p(x)=−2x2+40x−72, which models the fish population in thousands. We need to find the values of x for which p(x)=0. This means we need to solve the quadratic equation−2x2+40x−72=0.
Quadratic equation: To solve the quadratic equation, we can use the quadratic formulax=2a−b±b2−4ac, where a=−2, b=40, and c=−72.
Calculating the discriminant: First, we calculate the discriminant, which is b2−4ac. Plugging in the values, we get discriminant:=402−4(−2)(−72)=1600−4(2)(72)=1600−576=1024
Using the quadratic formula: Now we take the square root of the discriminant, 1024, which is 32.
Calculating the values of x: We can now use the quadratic formula to find the two values of x. Plugging in the values, we get x=2×−2−40±32
Solving for x: Calculating the two possible values for x, we get x=−4−40+32 and x=−4−40−32.
Final result: Solving these, we get x=−4−8=2 and x=−4−72=18.The two temperatures at which the fish population is zero are 2 degrees Celsius and 18 degrees Celsius. Since we need to enter the lower temperature first, the lower temperature is 2 degrees Celsius and the higher temperature is 18 degrees Celsius.
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