Question 607008: If I am 26 and my daughter is 4 how old will I be when I am three times her age?
Answer by bucky(2189)   (Show Source):
You can put this solution on YOUR website! Your are at present 26 years old and your daughter is 4 years old.
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Some unknown number of years from now (call it x years) you will be 26 + x years old and your daughter will be 4 + x years old.
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At that point in time your age (26 + x) will be 3 times your daughter's age or 3 times (4 + x). Written in equation form, this equality is:
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26 + x = 3(4 + x)
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Do the distributed multiplication on the right side by multiplying 3 times each of the terms inside the parentheses. With that multiplication the equation becomes:
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26 + x = 12 + 3x
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To solve this equation, we collect the terms containing x by themselves on the left side, and the numbers or constants by themselves on the right side. Do this by subtracting 3x from both sides and also subtracting 26 from both sides. This subtraction is as shown below:
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26 - 26 + x - 3x = 12 - 26 + 3x - 3x
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On the left side of the equation the 26 - 26 cancel each other out and the x - 3x combines to be - 2x. The left side becomes as shown in the equation below:
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-2x = 12 - 26 - 3x
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On the right side the 12 - 26 combine to -14 and the 3x - 3x cancel out to zero. Therefore, the right side of the equation is as shown in the equation below:
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-2x = -14
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Solve for x by dividing both sides by -2. When you do that division the equation becomes:
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x = -14/-2
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and this simplifies to:
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x = 7
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This translates to telling you that 7 years from now you will be 33 years old (26 + 7) and your daughter will be 11 years old (4 + 7). At that point in time you will be 3 times older than your daughter (3 times 11 equals 33). So this is the answer to the problem. You will be 33 years old when you are 3 times your daughter's age.
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Hope this helps you to understand the problem and shows you a proces you can use to solve it.
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