How do you write the direct variation of (-3, 9)?

Related questions

• What is Direct Variation?
• What does direct variation look like on a graph?
• What are examples of direct variation?
• How do you determine if a function is a direct variation when given a table?
• How do you write direct variation equations?
• What is the constant of proportionality "k"?
• Why is #y=2x-1# not a direct variation?
• How do you graph the direct variation equation #y=-\frac{1}{6}x#?
• What is the direct variation equation if y varies directly with x, and #y=7.5# when #x=2.5#?
• What is the direct variation equation if y varies directly with x, and #y=2# when #x=4#?