Find the points of intersection between the following equations for straight lines using the substitution method. y=x+5 and 5x-y=-1 & y=x-3 and 2x-y=7 thx
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Originally Posted by Mr Rayon Find the points of intersection between the following equations for straight lines using the substitution method. y=x+5 and 5x-y=-1 & y=x-3 and 2x-y=7 thx EQ1: You know that y=x+5, so substitute "x+5" in for y in the other equation 5x-y=-1 5x-(x+5)=-1 5x-x-5=-1 4x-5=-1 4x=4 x=1 Now just substitute "1" in for x in either equation 5x-y=-1 5(1)-y=-1 5-y=-1 -y=-6 y=6 Now you try for the second equation.
Is this right? y=x-3 2x-y=7 2x-(x-3)=7 2x-x+3=7 x+3=7 -3 -3 x=4 y=4-3 y=1 So x=4 and y=1 (4,1)
Originally Posted by Mr Rayon Is this right? y=x-3 2x-y=7 2x-(x-3)=7 2x-x+3=7 x+3=7 -3 -3 x=4 y=4-3 y=1 So x=4 and y=1 (4,1) Yep, you got it! -Dan
oh i understand now
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