Benjamin H. answered 01/15/21
Math and Science Made Simple! Experienced, Knowledgeable Tutor
Let the equation to represent Sarah's savings be 100 - 8x.
The equation for Martin's account would be 12x.
We are looking for the week, x, in which the two accounts have the same amount of money.
To find this, we simply need to set the equations equal to each other: 100-8x = 12x.
Now we only need to solve for x.
Add 8x to both sides: 100 = 20x
Divide both sides by 20: x = 5
After 5 weeks, Martin and Sarah will have the same amount of money in their accounts. If you need to find how much that would be, you can plug your x value into either equation.