Question

Two skaters are practicing at the same time on the same rink. A coordinate grid is superimposed on the ice. One skater follows the path y = −2x + 32, while the other skater follows the curve y = −2x2 + 18x. Find all points where they might collide if they are not careful.

Answer 1

Answer:

The skaters will collide at the points;

(2,28) and (4,24)

Step-by-step explanation:

The points they might collide will be the points when both y are equal;

-2x + 32 = -2x^2 + 18x

2x^2 -18x -2x + 32 = 0

2x^2 -20x + 32 = 0

2x^2 - 16x - 4x + 32 = 0

2x(x -8) -4( x -8) = 0

(2x -4)(x -8) = 0

2x = 4 or x = 8

x = 4/2 or x = 8

hence; x = 2 or 8

Now let’s get the y value

at x = 2, just substitute into any of the 2

y = -2x + 32

y = -2(2) + 32

y = -4 + 32 = 28

at x = 4

y = -2(4) + 32

y = -8 + 32

y = 24

The points that they will collide are;

(2,28) and (4,24)