Algebra 1
4.6 Model Direct Variation
• Two variables x and y show direct variation provided y = ax. The nonzero number a is called the constant of variation, and y is said to vary directly with x. • In other words, direct variation is just like slope – intercept form except the y – intercept (b) is always zero.
Identify direct variation equations
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Algebra 1
Graph the direct variation equation.
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Algebra 1
Write a direct variation equation 3
Algebra 1
c. According to the graph, how much does it cost to make 50 copies?
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