how to do substitution

Sagot :

Example 1: Solve the following system by substitutionSolution:Step 1: Solve one of the equations for either x = or y =2x+3y=5, x+y=5 . We will solve second equation for y , x+y=5 .. y=5-x.Step 2: Substitute the solution from step 1 into the second equation. 2x+3(5-x)=5Step 3: Solve this new equation. 2x+15-3x=5,=, -x+15=5,=,-x=5-15,=, -x=-10, -(-x=-10), x=10..Step 4: Solve for the second variable.y=5-x,,= y=5-10 = ,y=-5
 solution is: (x, y) = (10, -5)