The equation $y+4x=100$y+4x=100​ represents your distance y (in meters) from the finish line x seconds after you begin your leg of a relay race. The equation $y+3.7x=94$y+3.7x=94​ represents your opponent's distance from the finish line. How far do you need to run to catch up with your opponent?

Respuesta :

Given:

Your distance y (in meters) from the finish line x seconds after you begin your leg of a relay race is

[tex]y+4x=100[/tex]

Opponent's distance is

[tex]y+3.7x+94[/tex]

To find:

The distance you need to run to catch up with your opponent.

Solution:

We have,

[tex]y+4x=100[/tex]            ...(i)

[tex]y+3.7x+94[/tex]          ...(ii)

Subtract (ii) from (i), we get

[tex]y+4x-y-3.7x=100-94[/tex]

[tex]0.3x=6[/tex]

Divide both sides by 0.3.

[tex]x=\dfrac{6}{0.3}[/tex]

[tex]x=20[/tex]

Put x=20 in (i).

[tex]y+4(20)=100[/tex]

[tex]y+80=100[/tex]

[tex]y=100-80[/tex]

[tex]y=20[/tex]

They will meet at (20,20). It means at 20 meters from the finish line after 20 seconds from the beginning.

Put x=0 in (i), we get

[tex]y+4(0)=100[/tex]

[tex]y=100[/tex]

It means, initially the total distance you and finish line is 100 meters.

You will catch your opponent 20 meter from the finish line. So,

[tex]100-20=80[/tex]

Therefore, you need to run 80 meters to catch up with your opponent.