Question 3) suppose that a person drives 20 miles to work each day along a highway. in the morning the person drives the highway at the speed limit. in the evening there is lots of traffic and the person drives at 30 miles per hour slower than the speed limit. their total commute time is 1 hour. what is the speed limit on the freeway? (hint: compose an rational equation to solve this).

The speed limit on the freeway is 60 miles/hour.

Step-by-step explanation:

Suppose, the speed limit on the freeway is   miles/hour.

We know that,

So, the time required in the morning to drive 20 miles hour.

Now, in the evening, the person drives at 30 miles per hour slower than the speed limit. That means, speed in the evening

So, the time required to drive 20 miles in the evening hour.

Given that, the total commute time is 1 hour. So, the equation will be......

Using zero-product property, we will get.......

Here we can't take , as the speed in the evening will become negative for

So, the speed limit on the freeway is 60 miles/hour.

597

step-by-step explanation:

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional