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Solve the pair of linear equation x/6+y/15=4 & x/3-y/12=19/4 |
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Answer» Step-by-step explanation: X/6 + y/15 =4. x/3 - y/12 =19/4. Multiply EQUATION (x/6 + y/15 = 4) by 30 both Left HAND side and right hand side. Now if you multiply Left hand side by 30 we get 30*(x/6 + y/15) = 30*x/6 + 30*y/15 =5x + 2Y. Now if we multiply Right hand side of the equation by 30 we get 4*30 = 120. Now if we multiply Left hand side of the equation x/3 - y/12 =19/4 by 12 we get 12*(x/3-y/12) =12*x/3-12*y/12 =4x-y. Now if we multiply Right hand side of the equation by 12 we get 12*(19/4) =3*19 =57. Now we got two new equations 5x+2y =120 and 4x-y = 57 Now multiply the equation 4x-y = 57 by 2 Both Left hand side and Right hand side we get 2*(4x-y) = 2*57. We get 8x-2y = 114. Now if we ADD 5x + 2y = 120 and 8x-2y = 114 both Left hand side and Right hand side we get 5x+2y+8x-2y = 120 + 114 13x =234 So x = 234/13 = 18. So if we substitute x= 18 in 5x+2y = 120 We get 5*18 +2y = 120 90 + 2y = 120 2y= 120-90 2y = 30 y = 15. So x= 18 and y = 15. Hope you understood. |
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