Answer:
2y
Explanation:
Simplifying
21x + -42y = 0
Solving
21x + -42y = 0
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '42y' to each side of the equation.
21x + -42y + 42y = 0 + 42y
Combine like terms: -42y + 42y = 0
21x + 0 = 0 + 42y
21x = 0 + 42y
Remove the zero:
21x = 42y
Divide each side by '21'.
x = 2y
Simplifying
x = 2y