Neshtalloidn
Answered

IDNStudy.com, ang iyong mapagkukunan ng mabilis at eksaktong mga sagot. Makakuha ng hakbang-hakbang na mga gabay para sa lahat ng iyong teknikal na tanong mula sa mga miyembro ng aming komunidad.

3. A car travels 20 kph faster than a truck. The car covers 350 km in two hours less than the time it takes the truck to travel the same distance. What is the speed of the car? How about the truck? a. car: 70 kph; truck: 50 kph b. car:50 kph , truck:70 kph c. car:60 kph, truck:60 kph d. car:80 kph; truck:40 kph​

Sagot :

Katlinnnnnidn

3. Let s = the speed of the truck

and (s+20) = the speed of the car

to get the time of each vehicle time = distance/speed

truck time = 350/s

car time = 350/(s+20)

Truck time - car time = 2 hrs so,

(350/s) - [350/(s+20)] = 2

LCD we can get

[350(s+20) - 350s]/s(s+20) = 2

then transpose the denominator

350(s+20) - 350s = 2s(s+20)

simplifying we can get

350s + 7000 - 350s = 2s^2 + 40s

then simplify more to become quadratic equation

2s^2 + 40s - 7000 = 0

to make it simplest divide the equation by 2

s^2 + 20s - 3500 = 0

by factoring we can get

s= 50 s=-70 (impossible because of the sign)

SO

SOs = 50 km/h is the speed of the truck

s + 20 = 70 km/h is the speed of car

Ang iyong presensya ay mahalaga sa amin. Magpatuloy sa pagtatanong at pagbibigay ng mga sagot. Sama-sama tayong lumikha ng isang komunidad ng karunungan at pagkatuto. May mga katanungan ka? Ang IDNStudy.com ang may sagot. Bisitahin kami palagi para sa pinakabagong impormasyon.