Question

Can someone please help me.

10. The S-Cargo shipping company calculates shipping charges using the linear model, y = 2.72x, where y is the cost in dollars and x is the weight of the package in pounds (1 ≤ x ≤ 9). Use the linear model to compute the weight of a package with a shipping cost of $21.76. Round to the nearest hundredth of a pound, if necessary.



11. Two cars are 270 miles apart and travel toward each other on the same road. They meet in 3 hours. One car travels 2 mph faster than the other. What's the average speed of each car?



12. A line contains the point (4, 5) and is perpendicular to a line with a slope of -2/3. Write an equation of the line satisfying the given conditions. Write the answer in slope-intercept form.



13. Solve the equation: 6 - 3(-2 - 4x) = 2(3(x - 4) + 7)



14. A freight train and a passenger train leave a rail yard at the same time and travel on parallel tracks. The passenger train travels 6 mph faster than the freight train. The combined distance traveled after 2 hours is 100 miles. What's the average speed of each train?



15. A line contains the point (-3, -4) and is perpendicular to a line with a slope of 3/5. Write an equation of the line satisfying the given conditions. Write the answer in slope-intercept form.



16. Solve for the variable x.

F = kx - kx0

Answer 1

I will give you everything I can do:

11)

Lets say Car A travels at x mph. That means Car B travels at x+2 mph.

Both of them are traveling towards each others, so we can say the total speed is 2x+2.

Now i takes 3 hrs and we know the distance.

Since R*T=D

Then 3(2x+2)=270

So 2x+2=90

2x=88

x=44

12)

To find perpendicular we want to find the opposite reciprocal of the original slope. Therefore the slope is 3/2.

Now we must find the equation of the line with the given variable.

First find b.

5=3/2*4+b

b = -1

So the equation of this line is:

y=3/2x-1

13) All work will be shown below.

6-3(-2-4x)=2(3(x-4)+7)

6+6+12x=2(3x-12+7)

12+12x=2(3x-5)

12+12x=6x-10

6x=-2

x = -1/3

14)

First we must find the amount each train traveled.

The speed of F train(Freight train)=x

The speed of P train(passenger train)=x+6

Their combined speed is 2x+6

It takes 2 hrs to cover 100 miles

So 2(2x+6)=100

2x+6=50

2x=44

x=22

So the freight train covered 44 miles and the passenger train covered 56 miles.

To find average speed you must do Total Distance/Total Time.

44/2 and 56/2

Which are 22 and 28.

The average speed of F train is 22 mph and average speed of P train is 28 mph.

15) Again opposite reciprocal.

3/5 -> -5/3

Work:

-4=-3*-5/3+b

-4=5+b

b=-9

y = -5/3x-9

16)

F=kx-kx0

First kx0 = 0

So F=kx

So x=F/k