Express the equation in standard form. 1.x^2+y^2-2x-4y+1=0 2.5x^2+5y^2-8x-4y-121=0?
回答 (2)
2016-05-01 9:48 am
You say "equation" but I have worked out that there are in fact TWO equations crammed together !
Have also worked out that it is not 2•5 x^2
However here we go:-
1.
[ x² - 2x + 1 ] + [ y ² - 4y + 4 ] = 5 - 1
[ x - 1 ] ² + [ y - 2 ] ² = 4
2.
x ² - (8/5) x + y ² - (4/5) y = 121 / 5
x²-(8/5)x+16/25+y²-(4/5)y+4/25=121/5 + 20/25
[ x - 4/5 ] ² - [ y - 2/5 ] ² = 625/25
[ x - 4/5 ] ² - [ y - 2/5 ] ² = 25
Hope this helps--------take care with presentation !
Have also worked out that it is not 2•5 x^2
However here we go:-
1.
[ x² - 2x + 1 ] + [ y ² - 4y + 4 ] = 5 - 1
[ x - 1 ] ² + [ y - 2 ] ² = 4
2.
x ² - (8/5) x + y ² - (4/5) y = 121 / 5
x²-(8/5)x+16/25+y²-(4/5)y+4/25=121/5 + 20/25
[ x - 4/5 ] ² - [ y - 2/5 ] ² = 625/25
[ x - 4/5 ] ² - [ y - 2/5 ] ² = 25
Hope this helps--------take care with presentation !
2016-05-01 8:21 am
收錄日期: 2021-04-23 22:04:42
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https://hk.answers.yahoo.com/question/index?qid=20160501001026AACBX9a