Whats the ordered pair form of this equation 2x+5y=16 and -5x-2y=2?

1 Answer
Aug 24, 2017

Assuming that what you want is the ordered pair for the point of intersection of the two given lines:
#color(white)("XXX")(x,y)=color(red)(""(-2,4))#

Explanation:

#{: (color(blue)(2x+5y=16),"after multiplication by " 5 " gives",color(white)("x")color(blue)(10x+25y=80)), (color(blue)(-5x-2y=2),"after multiplication by "2" gives",ul(color(blue)(-10x-4y=color(white)("x")4))), (,"adding the revised forms of the two equations:",color(blue)(21y=84)), (,rarr color(blue)(y=84/21=4),) :}#

Similarly
#{: (color(blue)(2x+5y=16),"after multiplication by " 2 " gives",color(white)("x")color(blue)(4x+10y=32)), (color(blue)(-5x-2y=2),"after multiplication by "5" gives",ul(color(blue)(-25x-10y=color(white)("x")4=10))), (,"adding the revised forms of the two equations:",color(blue)(-21x=36)), (,rarr color(blue)(x=-42/21=-2),) :}#