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# simple maths question? Watch

1. what am i doing wrong guys...

(quadratic graphs)

y = x2 + 2x -3

for values of x from -4 to 2...

the y values are right in front of me and im putting the negative x values into my calculator and coming up with incorrect y values?

why is this guys?

thanks in advance
2. If you square a negative number, the answer will always be positive.
On a calculator, if you square a negative number the answer comes up as negative, but this is wrong.
You can't have a negative square number.
Hope this helps

Posted from TSR Mobile
3. (Original post by georgelewiss)
If you square a negative number, the answer will always be positive.
On a calculator, if you square a negative number the answer comes up as negative, but this is wrong.
You can't have a negative square number.
Hope this helps

Posted from TSR Mobile
wow just as you posted i found this out myself by typing -4 x -4 in the calculator coming up as 16

surely this is misleading is people dont know that though?

thanks for reply bro
4. (Original post by ThePremierLeague)
what am i doing wrong guys...

(quadratic graphs)

y = x2 + 2x -3

for values of x from -4 to 2...

the y values are right in front of me and im putting the negative x values into my calculator and coming up with incorrect y values?

why is this guys?

thanks in advance
when entering a negative value into a calculator and squaring it remember to put brackets outside to get a positive number (and hence the correct answer!).
e.g. instead of typing in into your calculator type in: to give 4 instead of -4.
5. (Original post by ThePremierLeague)
wow just as you posted i found this out myself by typing -4 x -4 in the calculator coming up as 16

surely this is misleading is people dont know that though?

thanks for reply bro
-4*-4 is 16, people do know that; you probably haven't learnt it.
Have a look at this site: http://www.cimt.plymouth.ac.uk/proje...5/bk7_15i2.htm
6. (Original post by nm786)
when entering a value into a calculator and squaring it remember to put brackets outside to get a positive number (and hence the correct answer!).
e.g. instead of typing in into your calculator type in: to give 4 instead of -4.
thanks dude
7. Put brackets around the number then square all

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