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bubbleduck99
Oct 29, 2007, 02:32 PM
how would you go about solving 6x+7y=19 and x+y=5?
I need to use the subsitution method. Please help! I don't understand this and I feel so stupid. :(

thank you :confused:
Carly ;)

mxwife28
Oct 29, 2007, 06:50 PM
how would you go about solving 6x+7y=19 and x+y=5 ??
i need to use the subsitution method. please help! i dont understand this and i feel so stupid. :(

thank you :confused:
Carly ;)
6x+7y=19_x+y=5

6x+7y=19_x=-y+5

6(-y+5)+7y=19_x=-y+5

(6(-y)+6(5))+7y=19_x=-y+5

(-6y+30)+7y=19_x=-y+5

y+30=19_x=-y+5

y=-30+19_x=-y+5

y=-11_x=-y+5

y=-11_x=-(-11)+5

y=-11_x=11+5

y=-11_x=16

y=-11_x=16

shorty777
Nov 1, 2007, 08:24 PM
6x+7y=19
x=2 y=1

x+y=5
x=3 y=2
or
x=2 y=3

hope this helps