The ray is reflected so that the angle of incidence a between the incident ray and the tangent to the parabola at (a, b) is equal
to the angle of reflection between the reflected ray and the tangent (Snell's Law).
A. Using the pictures above as a guide, find an expression for the slope of the line supporting the
reflected ray as a function of a.
slope =
B. Find the slope-intercept equation of the line supporting the reflected ray.
C. Find the coordinates of the point F common to all the reflected rays (this is the property that
motivates parabolic antennas and reflectors). F is called the focus of the parabola.
D. Find the distance between (a, b) and F as a function of a. Simplify your answer.
Dp =
1
E. Let D be the line y = Find the distance between (a, b) and D as a function of a. The line
4
D is called the directrix of the parabola.
Dp

answer: c, the green line

step-by-step explanation:

there is no black line, eliminate b.

simple interest implies periodic payments, but the red line shows no payments, eliminate d.

simple interest has equal payments. if paid say every day, the graph is about a straight line (actually a stairstep).

the yellow line is not straight, eliminate a.

check: the green line is straight, answer is c.

simple interest with positive interest rate gives a straight line sloping up to the right. green line:

g(t) = $100 + ($200-$100) ÷ (20 years) × (t years)

= $100 + (4%/year) × ($100)(t years)

incidentally, the yellow line curving upward represents continuously compounded interest

y = $100 × 2^(t years / (14 assuming the yellow line hits $200 at 14 years. 2^0 is 1, so y(0) = $100; 2^(14/14) is 2, so y(14) = $200.

question: use the following table of a school bus during morning pickups to calculate its average speed between 2.8 km and 4.2 km

answer: 42 km/h

explanation: 1.4/0.033 42.42424 = 42 km/h

question answered by

(jacemorris04)

hello, it is c -4

hope i you have a good day