Answer:
D.The function is decreasing for all real values of x where x < 1.5
Step-by-step explanation:
The vertex is at x=1.5, so the function is decreasing on one side of that and increasing on the other. Any answer choice with some number other than 1.5 as the boundary of increasing/decreasing can be ignored.
Of course one descriptor (<em>increasing</em> or <em>decreasing</em>) is not applicable for any interval that includes the point where the slope changes sign.
The function is decreasing for all real values of x where x < 1.5.
Answer: approximately 5.1818 pounds per square inch (psi)
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Work Shown:
P = pressure
T = temperature
The pressure is directly proportional to the temperature, which means P = k*T where k is some constant. As T goes up, P goes up as well, and vice versa. If P goes down, then T goes down too (or vice versa). In short, P and T go up together or go down together.
We're told that 6 psi (pounds per square inch) correspond to a temperature of 440 degrees F. This means P = 6 and T = 440 pair up. Let's use this P and T pairing to find k.
P = k*T
6 = k*440
6/440 = k
k = 6/440
k = 3/220
Therefore, the equation
P = k*T
updates to
P = (3/220)*T
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The last step is to plug in T = 380 to figure out the paired value of P
P = (3/220)*T
P = (3/220)*380
P = 5.1818 approximately
