- #1

harpazo

- 208

- 16

- Homework Statement
- Set up a system of equations to find the ages of Martin and his brother Luther.

- Relevant Equations
- M = 4L

M + 10 = 2(L + 10)

Martin is four times as old as his brother Luther at present. After 10 years he will be twice the age of his brother. Find their present ages.

Let M = Martin

Let L = LutherMartin is four times as old as his brother Luther at present.

M = 4L

After 10 years he will be twice the age of his brother.

M + 10 = 2(L + 10)

I came up with the following equations:

M = 4L...Equation A

M + 10 = 2(L + 10)...Equation B

I will now replace M in Equation B with 4L.

4L + 10 = 2(L + 10)

4L + 10 = 2L + 204L - 2L = 20 - 10

2L = 10

L = 10/2

L = 5

Luther is 5 years old.

Martin is 4 times Luther's age or 4(5) is 20 years old.

Let M = Martin

Let L = LutherMartin is four times as old as his brother Luther at present.

M = 4L

After 10 years he will be twice the age of his brother.

M + 10 = 2(L + 10)

I came up with the following equations:

M = 4L...Equation A

M + 10 = 2(L + 10)...Equation B

I will now replace M in Equation B with 4L.

4L + 10 = 2(L + 10)

4L + 10 = 2L + 204L - 2L = 20 - 10

2L = 10

L = 10/2

L = 5

Luther is 5 years old.

Martin is 4 times Luther's age or 4(5) is 20 years old.