Uae the method of elomination th solve the following simulaneous equation.
( 2 x - 4 ) / 5 + ( y + 2 ) / 2 = ( x + 5 ) / 3 + ( 2 y + 1 1 ) / 9 = 7
Use the method of elimination to solve ...
2007-12-07 4:55 am
回答 (1)
2007-12-07 5:56 am
✔ 最佳答案
( 2 x - 4 ) / 5 + ( y + 2 ) / 2 = 72( 2 x - 4 ) + 5( y + 2 ) = 70
4x+5y-68=0 ---(1)
( x + 5 ) / 3 + ( 2 y + 1 1 ) / 9 = 7
3( x + 5 ) + ( 2 y + 1 1 ) = 21
3x+2y+5=0 ---(2)
3x(1)-4x(2):
3(4x+5y-68)-4(3x+2y+5)=0
7y-224=0
y=32 ---(3)
Put (3) into (2):
3x+2(32)+5=0
3x=-69
x=-23
參考: my math knowlege
收錄日期: 2021-04-13 14:39:18
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