Functions (general)

Recall that the length a spring stretches varies directly with the amount of weight attached to it. A certain spring stretches 5 cm when a 10-gram weight is attached. Write a direct variation equation relating the weight x and the amount of stretch y.

• y = 0.5x

• y= 2x

• y= 5x + 10

• y= 2x +5

Which of the following represent direct variation?

(Select all that apply)

• "y varies directly as x"

• y = kx

• y = k/x

• xy = k

Is this a direct variation?

y=2x

• Yes, it is in y=kx form & k=2

• No, it is not in y=kx form

• Yes, it is not in y=kx form

• No, it is in y=kx form & k=2

Determine the type of variation:

• Direct
• Inverse
• Neither

Choose the Direct variation equation

• $y=22x$

• $y=\frac{14}{x}$

• $y=5^x$

• $y=30-2x$

Which of the following represents inverse variation?

• y = kx

• y = k/x

• y = x/k

• y = mx + b

The table represents

• a direct variation

• an inverse variation

• neither a direct nor an inverse variation

• both a direct and an inverse variation

What type of variation is shown in this table?

• Neither

• Direct

• Inverse

Is this table a direct variation?

• Yes

• No

Do x and y show direct variation?

y = 5x

• Yes

• No