Answer:
a) 9.62m (3 s.f.)
b) 2.58m (3 s.f.)
Step-by-step explanation:
Please see attached picture for full solution.
Here the answers I hope this helps!
Jean's car :
(12 1/2) / (5/12) =
(25/2) / (5/12) =
25/2 * 12/5 =
150/5 =
30 miles per gallon
Miranda's car :
(20 5/7) / (5/7) =
(145/7) / (5/7) =
145/7 * 7/5 =
145/5 =
29 miles per gallon
most fuel efficient is Jean's car....it gets 30 miles per gallon
Vertex: (-5,-2); parabola opens up;
General form of the equation for a vertical parabola opening up is:
y-k = a(x-h)^2; knowing that the vertex is at (-5,-2), we can write:
y+2 = a(x+5)^2. We need to find the value of the coefficient a.
From the graph we see that y is 10 when x is approx. -1 3/4 (or -7/4).
subst. these values into y+2 = a(x+5)^2, we get:
10 + 2 = a(-7/4 + 5)^2, or 12 = a(13/4)^2, or 1 = a(169/16).
Solving for a: a = 16/169 = 0.09, or approx 16/160, or 1/10. Unfortunately, this is not close to any of the four answer choices.
I thought it best to try again, and fortunately my second try was correct:
10+2 = a(13/4)^2, or (169/16)a. Thus, 12 = a(169/16)
12
Solving for a: a = ------------- = 1.14. The answer choice closest to this is 1.
169/16
Answer A is correct.
