Solving Simultaneous Equations

Algebra SIMULTANEOUS EQUATIONS Step 4. Find the value of the other unknown by substituting the value of the first unknown into one of the original equations. Step 5. Check the solution by substituting the values of the two unknowns into the other original equation. Example: Solve the following system of equations using addition or subtraction. 5x + 6y = 12 3x + 5y = 3 Solution: Step 1. Make the coefficients of y equal in both equations by multiplying the first equation by 5 and the second equation by 6. 5(5x + 6y = 12) yields 25x + 30y = 60 6(3x + 5y = 3) yields 18x + 30y = 18 Step 2. Subtract the second equation from the first. 25x 30y 60 (18x 30y 18) 7x 0 42 Step 3. Solve the resulting equation. 7x = 42 7x = 42 7 7 x = 6 Rev. 0 Page 33 MA-02