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Elimination 2x + 5y = 7 and 3x + 2y = 3 |
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Answer» Answer: 3X+2y = 3. (2) We need to make the coefficient same Hence, Multiply equation (1) by 2 or 3 ( because any of the variables can be made same) Let us take the no. 3 to multiply with equation (1) 3(2x + 5y =7) 6x + 15y = 21. (this Will be equ. 3) Same , coefficient in equation (2). should me made same So, Let us take the no. 2 to make coefficient same ( here we can take only 2 because we are making the coefficient same of variable X) Multiply equation (2) by 2 2(3x + 2y= 3) 6x+4y = 6. (this will be equ. 4) We have made the coefficient same We need to eliminate the variable X as it's coefficient is same . Therefore we will SUBTRACT the equation (3) and (4) Subtract equation (4) from(3) 6x +. 15y = 21 -. 6x +. 4y =. 6 (-). (-) ( Here 6x will be eliminated) Therefore, 11y = 15 y= 15÷11 y= 15/11 We need to find X therefore Substitute y= 15/11 in any equation We will take equation (2) 3x+ 2y= 3 3x + 2× 15/11 =3 3x+ 30/11= 3. ( 2×15/11 = 30/11 ) 3x = 3-30/11 3x= 3/11 X= 3/11÷3 X= 1/11 (X, y)= ( 1/11, 15/11) |
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