someone please help me on this...
Two cars traveled equal distances in different amounts of time. Car A traveled the distance in 2 h, and Car B traveled the distance in 1.5 h. Car B traveled 15 mph faster than Car A.
How fast did Car B travel?

Question

someone please help me on this...
Two cars traveled equal distances in different amounts of time. Car A traveled the distance in 2 h, and Car B traveled the distance in 1.5 h. Car B traveled 15 mph faster than Car A.
 How fast did Car B travel?

irishboy123 · Answer

$x_A = v_A \times t_A$
$x_B = v_B \times t_B$

$x_A = x_B \implies v_A \times t_A = v_B \times t_B$

$t_A = 2, \; t_B = 1.5$

$v_B = v_A + 15$

that kind of stuff :p

tootzrll · Answer

bruuuuhh im never gonna pass this... D,X

irishboy123 · Answer

you know that $distance = speed \times time$?  

right?

tootzrll · Answer

yes...

irishboy123 · Answer

ok so they travel the same distance, right?  at different speeds and using different times.

tootzrll · Answer

yes

irishboy123 · Answer

so, ..., distance travelled by  car A is $v \times 2 $

where v is the speed of the  car A

tootzrll · Answer

yes

irishboy123 · Answer

and that same distance, as travelled by  car B, is $ (v+15)×1.5$

that might be the confusing part...

tootzrll · Answer

wait, so whats the whole equation so far? i might have it by now...

irishboy123 · Answer

they travel the same distance

so you can say that

$$v \times 2 = (v+15)×1.5$$

or $2v = 1.5(v+15)$

irishboy123 · Answer

http://www.wolframalpha.com/input/?i=solve%2C+2v+%3D+1.5%28v%2B15%29

tootzrll · Answer

thanks a lot!! x)))

irishboy123 · Answer

v is the speed of car A

and you need the speed of car B

mentioned just in case

irishboy123 · Answer

$v_B = v + 15$