Final answer:
To solve the system of equations by substitution, substitute the value of x in terms of y into the other equation. Solve for y and substitute the value of y into the expression for x. The solution to the system is x = 10 and y = 5.
Step-by-step explanation:
To solve the system of equations by substitution, we need to find an equation in one variable from one of the equations and substitute it into the other equation. Let's solve the given system:
First, we have x = 2y. We can substitute this value of x into the other equation:
x + 4y = 30 becomes (2y) + 4y = 30. Simplifying, we get 6y = 30. Now, we can solve for y by dividing both sides by 6: y = 5.
To find x, we can substitute the value of y into x = 2y: x = 2(5) = 10.
Therefore, the solution to the system is x = 10 and y = 5.