Direct variation is a mathematical relationship where two variables increase...
Understanding Direct Variation in Algebra 1

Direct Variation
Direct variation occurs when two variables grow larger or smaller together at a consistent rate. The equation that represents this relationship is y = kx, where k is called the constant of variation and is never equal to zero.
To solve direct variation problems, you need to find the constant k using given values, then substitute this constant into the equation. For example, if x and y vary directly and y = 10 when x = 2, you can find k by solving 10 = k(2), which gives k = 5. The equation becomes y = 5x, allowing you to find y for any value of x.
Let's look at another example: if y = 27 when x = 3, then 27 = k(3), so k = 9 and the equation is y = 9x. When x = 6, you can calculate that y = 54. Similarly, if y = 2 when x = 10, then k = 1/5 and the equation becomes y = x.
💡 Remember that direct variation always creates a straight line passing through the origin (0,0) on a graph. The constant k represents the slope of this line.
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Understanding Direct Variation in Algebra 1
Direct variation is a mathematical relationship where two variables increase or decrease together at a constant rate. This relationship is expressed through a specific equation formula and helps us predict how changes in one variable affect another.

Direct Variation
Direct variation occurs when two variables grow larger or smaller together at a consistent rate. The equation that represents this relationship is y = kx, where k is called the constant of variation and is never equal to zero.
To solve direct variation problems, you need to find the constant k using given values, then substitute this constant into the equation. For example, if x and y vary directly and y = 10 when x = 2, you can find k by solving 10 = k(2), which gives k = 5. The equation becomes y = 5x, allowing you to find y for any value of x.
Let's look at another example: if y = 27 when x = 3, then 27 = k(3), so k = 9 and the equation is y = 9x. When x = 6, you can calculate that y = 54. Similarly, if y = 2 when x = 10, then k = 1/5 and the equation becomes y = x.
💡 Remember that direct variation always creates a straight line passing through the origin (0,0) on a graph. The constant k represents the slope of this line.
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