Home > Algebra > Direct Variation

For the direct variation y = 3 when x = -2, how do you find the constant of variation and find the value of y when x = 3?

Answer 1

Ethan Adkins

#y = -4.5#

# y prop x or y = k *x ; y=3 , x = -2 :. 3 = -2*k or#

# k = -3/2 :. y = -3/2 *x ; k# is known as constant of variation.

# x =3 , y = ? y = -3/2 *x :. y = -3/2 *3 =-9/2 = -4.5#

#y = -4.5# [Ans]

By signing up, you agree to our Terms of Service and Privacy Policy

Answer 2

Nathan Axel

To find the constant of variation ( k ), you divide the value of ( y ) by the value of ( x ) when they are both given. Then, to find the value of ( y ) when ( x = 3 ), you multiply the constant of variation by the value of ( x ).

Given ( y = 3 ) when ( x = -2 ): [ k = \frac{y}{x} = \frac{3}{-2} = -\frac{3}{2} ]

Now, to find ( y ) when ( x = 3 ): [ y = k \times x = -\frac{3}{2} \times 3 = -\frac{9}{2} ]

By signing up, you agree to our Terms of Service and Privacy Policy

Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.