SOLUTION: Within 11 years, the age of Peter will be half the square of the age he was 13 years ago. Calcute the current age of age

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Question 1164289: Within 11 years, the age of Peter will be half the square of the age he was 13 years ago. Calcute the current age of age
Found 2 solutions by ankor@dixie-net.com, ikleyn:
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website!
Within 11 years, the age of Peter will be half the square of the age he was 13 years ago.
Calculate the current age of Peter
:
a + 11 = .5(a-13)^2
a + 11 = .5(a^2 - 26a + 169)
multiply both sides by 2
2a + 22 = a^2 - 26a + 169
arrange as a quadratic equation
0 = a^2 - 26a - 2a + 169 - 22
a^2 - 28a + 147 = 0
Factors to
(a-7)(a-21) = 0
The reasonable solution
a = 21 yr is Peter's age
:
:
:
See if that works
a + 11 = .5(21-13)^2
a + 11 = .5(8^2)
a + 11 = .5(64)
a + 11 = 32
Yes, 21 + 11 = 32

Answer by ikleyn(52778)   (Show Source):
You can put this solution on YOUR website!
.

For your info :

        "within" means "inside of something", or "between".

        This word is INAPPLICABLE in the context of your problem.

        You should write "In 11 years . . . ", which means "11 years later", or "after 11 years".