90 likes | 149 Views
Because xy = 4 can be written in the form y = , xy = 4 represents inverse variation. The constant of variation is 4. a. x. y =. 4. x. EXAMPLE 1. Identify direct and inverse variation. Tell whether the equation represents direct variation , inverse variation , or neither.
E N D
Because xy = 4 can be written in the form y =, xy = 4 represents inverse variation. The constant of variation is 4. a x y = 4 x EXAMPLE 1 Identify direct and inverse variation Tell whether the equation represents direct variation, inverse variation, or neither. a. xy = 4 SOLUTION xy = 4 Write original equation. Divide each side by x.
= x b. = x y y y 2 y 2 2 Because= xcan be written in the formy = ax, = x represents direct variation. 2 EXAMPLE 1 Identify direct and inverse variation Tell whether the equation represents direct variation, inverse variation, or neither. SOLUTION Write original equation. y = 2x Multiply each side by 2.
Because y = 2x + 3cannot be written in the formy = or y =ax, y = 2x + 3 does not represent either direct variation or inverse variation. a x EXAMPLE 1 Identify direct and inverse variation Tell whether the equation represents direct variation, inverse variation, or neither. c.y = 2x + 3 SOLUTION
2x ANSWER inverse variation for Example 1 GUIDED PRACTICE Tell whether the equation represents direct variation, inverse variation, or neither. 1.y =
ANSWER direct variation for Example 1 GUIDED PRACTICE 2. 4y = 3x
ANSWER neither for Example 1 GUIDED PRACTICE 3. 5x – y = 3
12 ANSWER inverse variation for Example 1 GUIDED PRACTICE 4. xy =