Answer:
a = 10 or a = -10
Step-by-step explanation:
a^-2 = 1/100
We know 100 = 10^2
a^-2 = 1/10^2
We know 1/b^c = b^-c
1/a^2 = 1/ 10^2
Multiply by a^2 on each side
a^2 *1/a^2 = 1/ 10^2 *a^2
1 = a^2/10^2
Multiply by 10^2 on each side
1 0^2= a^2/10^2 * 10^2
10^2 = a^2
Take the square root of each side
sqrt(10^2) = sqrt(a^2)
±10 =a
Answer:
Step-by-step explanation:
The vertex and focus are horizon aligned, so the parabola is horizontal and the directrix is a vertical line.
The vertex is halfway between focus and directrix. Directrix: x = -4
Answer:
(A) 46 seconds
Step-by-step explanation:
You can arrive at an answer to this question at least two ways:
<h3>1)</h3>
Read the time from the graph.
Locate 144 on the vertical scale, just below halfway from 140 to 150. Locate the point on the graph that is at this vertical height. It is a little more than halfway between 40 and 50 on the horizontal scale.
The only answer choice in that neighborhood is t = 46 seconds.
__
<h3>2)</h3>
Use the given formula, and solve it for the time.
d = 1.5t +75
144 = 1.5t +75 . . . the distance of interest is 144
69 = 1.5t . . . . . . . .subtract 75
69/1.5 = t = 46 . . . seconds