Solve the following system of equations. Explain which method you used and why you chose that method 10x-6y=2 5x+3y=5
I have a suggestion. The addition method is practical to use when, by adding the equations, a variable is eliminated.
That can be done easily here. Notice the first equation has the term -6y and the second equation has the term 3y. If you turn the term 3y of the second equation into 6y, then adding those terms would eliminate y, since 6y + (-6y) = 0. Since you need 6y in the second equation, multiply the entire second equation by 2. Then add the equations together.
Copy the first equation exactly as it is. Below it, write the second equation multiplied by 2. Then add the two equations.
what about 2 and 5, do I add both of them together too?
Yes, but remember that the 5 becomes 10 when you multiply the second equation by 2. I'll show it to you below. Here is the original system of equations: \(10x-6y=2 \) \(5x+3y=5\) Now we copy the first equation as it is. Below it, we write the second equation after multiplying it by 2 on both sides. \(10x-6y=2 \) \(10x+6y=10\) Now we add the two equations: \(20x + 0y = 12\) \(20x = 12\) Now that we have one equation in one variable, x, we solve for the variable. Divide both sides by 20: \(\dfrac{20}{20}x = \dfrac{12}{20}\) Reduce the fraction by dividing the numerator and denominator by 5. \(x = \dfrac{3}{5} \) Now that we have x, we can use the equations to eliminate x and solve for y. Let's go back to the step where the second equation had been multiplied by 2. The two equations are (copied form above): \(10x-6y=2 \) \(10x+6y=10\) Now we subtract the equations. The terms 10x in both equations will be eliminated leaving an equation in only y. Subtracting the equations we get: \(-12y = -8\) Divide both sides by -12 and reduce the fration: \(\dfrac{-12}{-12}y = \dfrac{-8}{-12}\) \(y = \dfrac{8}{12} \) \(y = \dfrac{2}{3} \) The solution is: \(x = \dfrac{3}{5} \), \(y = \dfrac{2}{3} \)
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