Homework Help: algebra

Posted by jordan on Thursday, October 15, 2009 at 12:40pm.

Yesterday Lucy walked 2 hours and jogged 1/2 hour and covered 6.25 miles. Today she walked for 3 hours and jogged for 1 hour and covered 10.25 miles. Assuming a constant walking rate and a constant jogging rate, how fast did she walk and how fast did she jog? Define two variables, write a system of equations, and solve to find the walking rate and the jogging rate.

2w + .5j= 6.25 --> 3(2w+.5j)= 3(6.25)
3w + 1j= 10.25 --> -2(3w+1j)= -2(10.25

6w + 1.5j= 18.75>> -.5j=-1.75
6w + 2j= -20.50 >> j=.3

2w + .5(.3)= 6.25
2w + 15= 6.25
2w= 6.10 w= 3.05

check:
2(3.05) + .5(.3)= 6.25 (correct)
3(3.05) + 1(.3)= 9.45(wrong!!) it should be 10.25.

please tell me where im going wrong:)

algebra - bobpursley, Thursday, October 15, 2009 at 1:10pm
I am lost here:
6w + 1.5j= 18.75>> -.5j=-1.75
6w + 2j= -20.50 >> j=.3

I think you should have
6w + 1.5j= 18.75>>
-6w - 2j= -20.50 >>
adding them,
.5j= 1.75
j= .35
and w= you do it.
messed up,,,redo. - jordan, Thursday, October 15, 2009 at 1:13pm
w- walking j- jogging
2w + .5j= 6.25 --> 3(2w+.5j)= 3(6.25)
3w + 1j= 10.25 --> -2(3w+1j)= -2(10.25

6w + 1.5j= 18.75
-6w - 2j= -20.50
-----------------
-.5j=-1.75
j=.3

2w + .5(.3)= 6.25
2w + 15= 6.25
2w= 6.10 w= 3.05

check:
2(3.05) + .5(.3)= 6.25 (correct)
3(3.05) + 1(.3)= 9.45(wrong!!) it should be 10.25.

Answer this Question

Related Questions

algebra...redo. - Yesterday Lucy walked 2 hours and jogged 1/2 hour and covered ...
11th grade - Yesterday Lucy walked 2 hours and 1/2 jogged hour and covered 6.25 ...
math - Yesterday Lucy walked 2 hours and jogged 1/2 hour and covered 6.25 miles...
algebra - Jean jogged for 2 miles and then walked for 3 miles. Took her 1 1/3 ...
math - Tom and kate live 15 miles apart they decide to jog to meet eachother ...
ALGEBRA II - George jogged downhill at 6mi/hr and then jogged back up at at 4mi/...
math - I have 1 question I just can't seem to solve:A rabbit and a tortoise ...
algebra - write a linear equation to model the situation. you have walked 4 ...
HELP ON MATH PLEASE!!!!!!! - John jogged downhill at 6mi/hr and then jogged back...
Math - You walk at 4 miles per hour for 1/2 hour, and then jog at 6 miles per ...

For Further Reading

First Name:
School Subject:
Answer: