Two car starts from points 420 miles apart and travelled toward each other. they meet after 3.5 hours . find the average rate of faster car if one travels 30mph slower than the other.

the speed of the faster car is 75 miles per hour

Step-by-step explanation:

Initially, the distance between the two cars before they travelled towards each other is 420 miles.

Let x represent the speed of the slower car.

Let y represent the speed of the faster car.

Find the average rate of faster car if one travels 30mph slower than the other. This means that

y = x + 30

They meet after 3.5 hours.

Distance travelled = speed × time

Distance travelled by the slower car is x × 3.5 = 3.5x miles.

Distance travelled by the faster car is y × 3.5 = 3.5y miles. Since the total distance travelled by both cars is 420 miles, therefore,

3.5x + 3.5y = 420

x + y = 120 - - - - - - - - - - -1

Substituting y = x + 30 into equation 1, it becomes

x + x + 30 = 120

2x = 120 - 30 = 90

x = 90/2 = 45

y = x + 30

y = 45 + 30 = 75

step-by-step explanation:

given perimeter: 28cm

length: 9cm

atp,

2(l+w)=p of the reactangle

2(9+x)=28

18+2x=28

2x=28-18

x=10/2

x=5

therefore width is 5 cm