11x+15y+23=0,7x-2y-20=0 solve it elimination method

1.	11x+15y+23=0,7x-2y-20=0 solve it elimination method
Answer» The given system of equations is11x + 15y + 23 = 0 ....(1)7x - 2y - 20 = 0 ....(2)To solve the equations (1) and (2) by cross multiplication method,we draw the diagram below:Then,{tex}\\Rightarrow \\;\\frac{x}{{(15)( - 20) - ( - 2)(23)}} = \\frac{y}{{(23)(7) - ( - 20)(11)}}{/tex}{tex}= \\frac{1}{{(11)( - 2) - (7)(15)}}{/tex}{tex}\\Rightarrow \\;\\frac{x}{{ - 300 + 46}} = \\frac{y}{{161 + 220}} = \\frac{1}{{ - 22 - 105}}{/tex}{tex}\\Rightarrow \\;\\frac{x}{{ - 254}} = \\frac{y}{{381}} = \\frac{1}{{ - 127}}{/tex}{tex}\\Rightarrow \\;x=\\frac{{ - 254}}{{ - 127}} = 2{/tex} and {tex}y = \\frac{{381}}{{ - 127}} = - 3{/tex}Hence, the required solution of the given pair of equations isx = 2, y = -3Verification : substituting x = 2, y = -3,We find that both the equations (1) and (2) are satisfied as shown below:11x + 15y + 23 = 11(2) + 15(-3) + 23= 22 - 45 + 23 = 07x - 2y - 20 = 7(2) - 2(-3) - 20= 14 + 6 - 20 = 0Hence, the solution we have got is correct. 14+6-20=0

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