Substitute your birthday into the equation Square root of the quantity x minus y + m = d, where y is the last two digits of your birth year, m is the month, and d is the day. If you were born on 7/10/1856 like Nikola Tesla, your equation would be Square root of the quantity x minus 56 + 7 = 10. Solve for x and identify if it is an extraneous solution. my7 bday is 3/8/1996
@whpalmer4
@helpme1.2
@radar
I've got an easy one: same month and same day, \(x = \text{year}\) :-)
@radar are you doing your birth year? you must be either much younger or older than you look :-) DI_KAZ' birth year is 96, not 93.
My year is 38 (1938) lol
if you were born a/b/cd, the problem is \[\sqrt{x-cd} + a = b\]
i got the qution \[\sqrt{x-96}+3=8\]
based on the Tesla example
Right, so how to solve \[\sqrt{x-96}+3=8\]I'd start by moving the 3 to the right hand side. Then you can square both sides and solve for \(x\).
can u show me the steps im a visaul learner
Okay, subtract 3 from both sides of the equation. What's the new equation?
from which sides the 93 and the 8?
96*
\[\sqrt{x-96} + 3 = 8\]Subtract 3 from both sides of the equation: \[\sqrt{x-96} + 3 - 3 = 8 -3\]\[\sqrt{x-96}=5\] Agreed? If we add or subtract the same quantity from both sides, the equation remains equivalent.
RIGHT
Okay, so to get rid of that pesky radical sign on the way to getting \(x=\) all alone, let's square both sides. They are equal, so they should be equal to each other after we square both sides, too. \[(\sqrt{x-96})^2 = 5^2\]But the square of the square root is just the value under the square root sign: \[x-96 = 5^2 \]\[x-96=25\] You can solve that for \(x\), right?
how?
here the ^2 come from
^2 came from squaring each side: I could also have written \[(\sqrt{x-96})(\sqrt{x-96}) = 5*5\]\[x-96 = 25\]
ok then what
Okay, you've got some money in your pocket. If you hand me 15 bucks, you'll have 10 left. How much money do you have in your pocket?
How much money would you need to have to be able to give me $15 and still have $10 for yourself?
5
If you had $5 in your wallet, you could give me $15 and have $10 left for yourself? I don't think so!
25
If you had $25 in your wallet, you could give me $15, and you would have $25-$15 = $10 left. That's exactly the form of the problem we are trying to solve. We've got some number, \(x\), and if we subtract 96 from it, we have 25 left.
\[x-96=25\]If we add 96 to both sides:\[x-96+96 = 25+96\]\[x + 0 = 25 + 96\]\[x=25+96\]\[x =\]
121
yes!
haha thanks
Now we have to test our answer in the original problem to see if it works, or if it is an extraneous solution (read: it doesn't work) \[\sqrt{121-96} +3 = 8\]\[\sqrt{25}+3=8\]What is the square root of 25?
what number when multiplied by itself gives you 25 as the answer?
5
Right. \[5+3=8\]True or false?
@DI_KAZ Does the DI stand for Drill Instructor??
true and yes i want to be one it helps me keep my goals in sight if i see it alot
Good goal.
thanks
You're welcome. whpalmer4 really laid that problem out. Good luck with your studies.
thanks and thanks @whpalmer4
My kid brother was a Marine Harrier pilot during the first Gulf War. Semper Fi!
that awesome !!!
tag me if you ever get stuck on a problem, and I'll try to help you out when I'm next available.
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