Distance = speed times time distances is equal so (x-5)(4.5)=(x)(4) 4.5x-22.5=4x multiply both sides by 2 to get rid of the decimals 9x-45=8x subtract 8x from both sides x-45=0 a add 45 to both sides and get x=45 speed of car A = 45 mph Speed of car B = 45-5 or 40 mph Speed of car B = 40 mph