Answer:
Step-by-step explanation:
-2/7x -5 =13
-2/7x = 13 + 5 = 18
x = 18 (-2/7)
x = -5.14
Answer:
342in
Step-by-step explanation:
Answer:
Step-by-step explanation:
Since the coefficient of x^2 is positive, this quadratic is a parabola in the shape of a U, hence has a minimum.
We want to end up with the form (x-h)^2 + c. Since (x-h)^2>=0, this form shows that the minimum is achieved when x=h.
Completing the square will put the quadratic in the desired form. Note that:
(x-h)^2=x^2-2hx+h^2
Comparing this with the given form, we must have -8=-2h, or h=4. But we are missing h^2=4^2=16. We can add the missing 16 and subtract it elsewhere without changing the quadratic.
x^2-8x+16 + (16-4) = (x-4)^2 + 12
Now we know that at x=4 the quadratic has a minimum and that the minimum is 12.
Answer: the first option is the correct answer.
Step-by-step explanation:
Martin runs 3/4 mile three days a week. We would assume that he runs a total of 3/4 miles in three days of each week.
In four weeks the number of days that he runs would be
3 × 4 = 12 days
Since he runs 3/4 miles in 3 days, the number of miles that he would run in 12 days would be
3/4 × 12 = 9 miles
He would run 9 miles in four weeks
