determine the resulting equation if one variable is solved in terms of the other variable in one equation and substitute this variable in the other equation.

Question

1.) 2x+5y=9
-x+y=2
2.) 3x+y=2
9x+2y=7
3.) x-y=-3
3x +y=19

Answer 1

#1 We see that x = y-2, so
2(y-2)+5y = 9

Do the others in like wise.