Direct and inverse variation | Rational expressions | Algebra II | Khan Academy

What is the general equation for direct variation between two variables, y and x, where k is a constant?

• y = k + x

• y = kx

• y = k/x

• y = x - k

In the equation y = 1/2x, what is the constant of variation (k)?

• 1

• 2

• 1/2

• x

Which of the following equations represents direct variation?

• y = x + 5

• y = 3/x

• y = -4x

• y - x = 2

If y varies directly with x, and x is doubled, what happens to y?

• y is halved

• y is doubled

• y remains the same

• y is multiplied by 4

What is the general form of a direct variation equation, where 'k' is a constant?

• y = k/x

• y = kx

• y = x + k

• y = k - x

Which of the following equations shows a direct variation?

• y = 5/x

• y = x - 3

• y = 4x

• y = x + 4

What is the general form of an inverse variation equation, where 'k' is a constant?

• y = kx

• y = k + x

• y = k/x

• y = k - x

Which of the following equations shows an inverse variation?

• y = 3x

• y = x + 2

• y = 7/x

• y = x - 7