Posted by saira on Monday, February 16, 2009 at 5:56pm.
solve the linear system using substitution. please show me the steps!:)
xy=5
2xy=7

gr.10 math  Reiny, Monday, February 16, 2009 at 6:09pm
arrange the first equation to x = y5
sub replace the x in the second equation with that expression
2xy=7
2(y5)  y = 7
2y  10  y = 7
y = 7 + 10
y = 3 , now let's put that back into x = y5
x = 3  5
x = 2
so x = 2, y = 3
check in the first:
is 2  (3) = 5 ? , yes!
in the second:
is 2(2)  (3) = 7 ? , yes!