To calculate the BAC, we first find the amount of alcohol (in grams) of the drinks. In the US, a standard drink has 14 g of alcohol. The man has 2 beers and 1 shot; this is 3 standard drinks: 3*14 = 42
This has 42 g of alcohol.
Next we convert the weight in pounds to grams. We do this by multiplying by 454: 140*454 = 63560
Next we multiply by the gender constant. For men, this is 0.68: 63560(0.68) = 43220.8
We divide the grams of alcohol by this number: 42/43220.8 = 0.000972
Multiply this by 100: 0.000972(100) = 0.0972
This is the BAC right after drinking. To account for the time that has passed, we multiply the number of hours by 0.015: 1(0.015) = 0.015
We subtract this from our immediate BAC: 0.0972-0.015 = 0.0822 ≈ 0.08
Around .8 B.A.C because if you look at scales online a 12 ounce beer is one drink and a 1 1/2 oz. shot is another full drinks. So that's 3 drinks which means its around a .8 for a 140 pound man.
The line of symmetry is the center/ middle of the parabola where the curve shifts. Since the line of symmetry is at x=2 and the zero is at x= -1, you have the find the difference between the values which is 3. So the other zero is three the right of the line of symmetry at x= 5.