hi i've got the question: solve the simultaneous equations $\displaystyle 2x + y = 9$ and $\displaystyle (x - 2)^2 + y^2 = 5$

can someone show me how this would be done please? thanks

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- Oct 19th 2009, 02:28 AMmarksimultaneous equations
hi i've got the question: solve the simultaneous equations $\displaystyle 2x + y = 9$ and $\displaystyle (x - 2)^2 + y^2 = 5$

can someone show me how this would be done please? thanks - Oct 19th 2009, 02:40 AMmathaddict
HI

$\displaystyle 2x+y=9$ --1

From 1 , $\displaystyle y=9-2x$

$\displaystyle (x-2)^2+y^2=5$

Substitute $\displaystyle (x-2)^2+(9-2x)^2=5$

$\displaystyle x^2-4x+4+81-36x+4x^2-5=0$

$\displaystyle x^2-8x+16=0$

$\displaystyle x=4$

$\displaystyle y=9-2(4)$

$\displaystyle

=1

$ - Oct 19th 2009, 04:50 AMstapel
Ouch! They were supposed to have covered this in class and in your text before assigning questions on it! (Wondering)

To learn "how this would be done", try**an online lesson or two**. Be sure to study the worked examples. (Wink)