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Steps for the Substitution Method

1. Choose an Equation and Solve for One Variable:
   • From one of the equations in the system, isolate one variable (ex: x,y….)
2. Substitute the Expression:
   • Replace the isolated variable in the other equation(s) with the expression obtained in Step 1.
3. Simplify and Solve:
   • Solve the resulting equation, which now has only one variable.
4. Back-Substitute to Find the Other Variable:
   • Use the value obtained in Step 3 and substitute it back into the expression from Step 1 to find the value of the other variable.
5. Check Your Solution:
   • Substitute the values of both variables into the original equations to verify the solution.

 

Try to solve: x+y=7    2x-y=4     using substitution