Determine whether the equation represents a direct variation. if it does, find the constant of variation:

1. 2y=5x+1
a. not a direct variation
b. direct variation, constant of variation is 5/2
c. direct variation, constant of variation is 2/5
d. direct variation, constant of variation is 1 -2/5

2. -12x=6y
a. not a direct variation
b. direct variation, constant of variation is ½
c. direct variation, constant of variation is 2
d. direct variation, constant of variation is -2

3. 0.7x-1.4y=0
a. not a direct variation
b. direct variation, constant of variation is ½
c. direct variation, constant of variation is 2
d. direct variation, constant of variation is -2

1) A. Not a direct variation 2) D. Direct Variation, constant of variation is -2 C) B. Direct Variation, constant of variation is ½

Step-by-step explanation:

Direct Variation requires that with k≠0. K its constant of variation and its slope. It is a linear function with b =0

1) Examining 2y =5x + 1. Rewriting it as standard form:

Since this function cannot be written as y=kx as b ≠ 0 (b=1) then we can say that this is not a direct variation.

A. Not a direct variation

2)

This linear function has no linear parameter. And its line goes through the origin varying directly. The constant k is equal to -2. So,

D. Direct Variation, constant of variation is -2

3)

The Constant of Variation is 1/2 and K>0. There is a direct variation between x and y of 1/2. So it's B.

B. Direct Variation, constant of variation is ½

the line of

the formula for the equation of a circle is (x – h)2+ (y – k)2 = r2, where (h, k) represents the coordinates of the center of the circle, and r represents the radius of the circle. if a circle is tangent to the x-axis at (3,0), this means it touches the x-axis at that point.