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# Help Simultaneous equation watch

1. x²+y²=17
3y+x=11

help solving this plsssssss
2. Rearrange the second one for x or y, x is easier, and then sub into first one and solve for y. And, haven't you already posted this?
3. Spoiler:
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x = 11 - 3y

(11 - 3y)² + y² = 17

6y² - 66y + 121 + y² = 17

7y² - 66y + 104 = 0

Complete square/use formula

hope i havent made a mistake there, the numbers are a bit gay in the quadratic
4. rearrange 3y+x=11, into x=11-3y
and substitute so (11-3y)^2 +y^2=17, multiply brackets out, simplify, and form a quadratic, obtain 2 y values, then substitute them both into x=11-3y, to obtain 2 x values
5. should be 9y^2 not 6y^2 zd000
6. (Original post by nathsen)
should be 9y^2 not 6y^2 zd000
haha knew i did something stupid in there xD
7. If you're looking for academic help, please post in the relevant academic help forum rather than the general secondary one .

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