# Algebra

posted by .

Each ordered pair is a solution of a direct variation. Write the equation of direct variation.
(2,10)
(8,2)
(7,21)
(2,-16)

• Algebra -

A direct variation is such that the ratio of y/x is always constant (but x≠0).

For example, the line
L: y=2x is a direct variation.
Points on the line could be (1,2),(2,4),(5,10), noting that the ratio x/y is always 1/2. Consequently, the line passes through origin.

The general equation of a direct variation is y=mx.

Given an ordered pair where x≠0 and y≠0, we can find m by substituting x and y into the general equation.

For example, for the point (2,10), we put 10=m(2), solving gives m=10/2=5.
The equation of the direct variation is therefore:
y=5x

I will leave the rest to you as an exercise.

• Algebra -

(x,8) and (6,-16) can you give me the answer that's all I need thanks

## Similar Questions

1. ### Algebra 2

Let (x1,y1) be a solution, other than (0,0), of a direct variation equation. Write an second direct variation equation whosegraph is perpindicular to the graph of the first equation.
2. ### Algebra

This is about direct variation. The area a painter can paint varies directly with the amount of time he works. One morninig, he painted 204 ft² between 8 a.m. and 12:15 PM. Write a direct variation equation to describe the area y …
3. ### math

This is about direct variation. The area a painter can paint varies directly with the amount of time he works. One morninig, he painted 204 ft² between 8 a.m. and 12:15 PM. Write a direct variation equation to describe the area y …
4. ### Math

Is the ordered pair (0,0) a solution of the direct variation equation y=kx ?
5. ### algebra

Tell whether equation represents direct variation. If so, identify the constant of variation 1. Y=8x Ans: yes, it represents direct variation because its in the form Y=kx. Constant of variation: 8 2. Y=2x+1 3. 3x+y=6 Please help, not …
6. ### Algebra 2

Is the relationship between the variables in the table a direct variation, an inverse variation, both, or neither?
7. ### Algebra worksheet

Hello. My algebra teacher gave me this worksheet last week and everyone had to bring it yesterday and I haven't done it yet. Can someone please help me. He said Friday is the last day or he's going to take away some points. I've been …
8. ### math

Is the relationship between the variables in the table direct variation, inverse variation, both, or neither?
9. ### Algebra

Does the data in the table represent a direction variation or an inverse variation, write an equation x 1 2 5 10 y 40 20 8 4 My answer is a direct variation, y=40x, is this correct?
10. ### Algebra 2

Evaluate the function when x=1. f(x)=4x-2. Write the input and output as a set of ordered pairs, and identify the domain and range of the ordered pair. Ordered Pair: Domain: Range: 2. Write an equation of direct variation that passes …

More Similar Questions