please help me with my math homework! Will give points to best answer!?

Question

set up an equation with variables for all or some of the problems. Show and explain your steps.
1. The length of a rectangle is twice its width. If the width is 6 inches, what is the length?
2. Ellen's age is 4 years less than 1/2 of her father's age. If Ellen is 15, how old is her father?
3. Elena and Emily together have $72. Elena has twice as much as Emily. How much money does each have?

PLEASE help solve these problems. I assure you that points will be given.
By the way I need the answers by tomorrow!
:)

please don't forget to give the steps!

Answer 1

L (length) = 2 W (width)
L = 6 inches
therefore 6 = 2W
6/2=W
3 =W

Ellen = E, D = Dad, or father
E = (D-4)/2
15 = (D-4)/2
2*15 = D - 4
(2*15) +4 = D
34 = D, Ellen's dad is 34 years old.

Elena = L, Emily = E
E + L = 72
L = 2E
substituting 2E for L, we get:

E + 2E =72
3E = 72
E =72/3
E=24

therefore Elena has $48 (2 * 24) and Emily has $24.

Answer 2

set up an equation with variables for all or some of the problems. Show and explain your steps.
1. The length of a rectangle is twice its width. If the width is 6 inches, what is the length?

L=legth, w=width
L=2w
L=2(6)
L=12

2. Ellen's age is 4 years less than 1/2 of her father's age. If Ellen is 15, how old is her father?

E=ellen's age, F=her father's age
E= 1/2F-4
15= 1/2F-4
15+4= 1/2F
19=1/2F
19x2=F
38=F
Ellen's father's age is 38

3. Elena and Emily together have $72. Elena has twice as much as Emily. How much money does each have?

Not sure how to list that one out.. sorry.

Answer 3

1.) If the width is 6 inches, multiply by 2. Therefore the length is 12 inches or 1 foot.

2.) If Ellen is 15, which is 4 years younger than half of her father's age, add four to her age. You get 19. 19 is half of his age so multiply by 2. Her father is 38.

3.) I had a funny way of figuring this out. I just divided 72 by 3 which is 24. Which means if 72 dollars was split between 3, each would have $24. But it's not split between 3. It's between 2. The reason I had it split between 3 was because Elena has TWICE AS MUCH. So Elena would have 2 thirds of the money. Which is $48. Emily has $24.

Answer 4

1) Sorry, too easy. Just think about it.

2) Let x=father's age. Then Ellen is 1/2x-4. Since she is 15, the equation would be 1/2x-4=15. Solve for x, and you have her father's age.

3) Let Emily be x. Then Elena has twice as much, or 2x. Together x+2x, they have 72. So, x+2x=72. Solve for x and get Emily and double it to get Elena.

Answer 5

length=2*width
x=2*6
x=12

1/2*father=ellen+4
2/1*(1/2*father)=(ellen+4)*2/1 (multiply by reciprocal)
father=(2*ellen)+(4*2) (distributive property)
father=(2*15)+(4*2) (substituting ellen's age)
father=30+8
father=38

(check: ellen's age plus 4 is 19. 19 should be half of her dad's age, so 19*2=38)

72=elena+emily (since the problem splits it into 3 parts, with elena taking 2 of the three parts and emily 1 part...)
elena=2x
emily=x

72=2x+x
72=3x (adding common factors)
72/3=3x/3 (dividing both sides by coefficient)
72/3=x
24=x

Substitute "x" for initial equations to find each girl's money.
So... Elena=2*24 which is $48
And... Emily=1*24 which is $24

(Check: 24+48=72 and 48=24*2)

If you need help with this you should REALLY ask your teacher. ;) I'm sure he or she would be more than happy to help you instead of having you turn to Yahoo! answers. ;) Also, these 3 questions will probably be worth way less than the test question's he/she will be asking you with no help from outsiders...

Answer 6

1. l=2w
w=6
l=(2)(6)
l=12
2. e+4=1/2f
e=15
15+4=1/2f
19=1/2f
f=38
f is the father's age, e is ellen's age
3. 2elana + 1 elena+72
3elana=72
elana=24
elana has 48, emily has 24
1 elena is the amount of money emily has

Answer 7

a million. 3x+9=27 what does x= ? x=6 First, subtract 9 from 9 and 27, to get 18, then divide 3 and 18 by utilising 3 to get x=6. All you're doing is keeping apart the variable. 2. -5y-4=seventy six what does y= ? -sixteen 3. 10-a million/4b=9 what's b= ? 4 4. 4c+7-6c=23 what does c= ? -8 This one, you integrate 4c and -6c (upload) to get .2c then you definitely do what I defined till now. 5. 13d-fifty 3=9d+19 what does d= ? Subtract the 9d from the 13d to get 4d-fifty 3=19 and do the different steps I defined. answer's 18. 5/6e+18-a million/6e=6 whats e? 25-3/9f=19+4/7f whats f? 3(y+4)-10=sixty six-5y what's y? Distribute. 3y+12-10=sixty six-5y so as that is 3y+2=sixty six-5y answer's -8 4(g-2)=2(g+8) what's g? Distribute returned. 4g-8=2g+sixteen answer is 12

Answer 8

I normally don't do homework, but I like points:

1. 12

2. 38

3. Elena 48, Emily 24

Points, please

Answer 9

12 and 38 i think but i have no idea what hte last one is sorry

Answer 10

That is not helping, that is doing it for you