Is this a direct variation?

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Is this a direct variation?
Course 2 Identifying DV Is this a direct variation? x y -2 -4 -1 1 2 4 x y 1 6 2 12 3 18 4 24 x y 3 6 5 10 7 14 4 8 12

Is this a direct variation?
Course 2 Identifying DV Is this a direct variation?

QUESTION How are direct variation problems solved using the equation?
Course 2 DV Problems Insert Lesson Title Here QUESTION How are direct variation problems solved using the equation?

To solve problems: DV Problems
If there is more than one set of data, make a t-table with the given information. Using the equation y = kx or the ratio k = y/x, substitute the known values. 3. Solve for k. Course 2

DV Problems Substitute the k value into direct variation equation.
Solve for the value of y. Course 2

Find an equation of direct variation.
Course 2 DV Problems Example: Find an equation of direct variation. y is when x is 4

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Course 2 DV Problems Insert Lesson Title Here Example: x varies directly with y. If y = 8 when x = 12, what is the value of y when x = 15? x y 12 8 15 ?

QUESTION How are direct variation problems solved using proportion?
Course 2 DV Problems Insert Lesson Title Here QUESTION How are direct variation problems solved using proportion?

DV Problems 1. Substitute given values into the proportion
2. Solve for the value of y using cross product. Course 2

Course 2 DV Problems Example: x varies directly with y. If y = when x = -2.5, what is the value of y when x = -8?

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Course 2 DV Problems Insert Lesson Title Here Practice Problems Find an equation of the direct variation when y is -64, x is 4. Find an equation of the direct variation when y is 6.3, x is 0.7 Find an equation of the direct variation when y is ½ , x is ¼ . y = -16x y = 9x y = 2x

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Course 2 DV Problems Insert Lesson Title Here Practice Problems x varies directly with y. If x = 5 when y = 4.45, what is the value of y when x = 7.12? x varies directly with y. If x = -2 when y = -3/2, what is the value of y when x = -4? x varies directly with y. If x = 5 when y = 4.5, what is the value of y when x = 1.5? y = y = -3 y = 1.35

Is this a direct variation?
Course 2 Identifying DV Is this a direct variation? x y -2 -4 -1 1 2 4 x y 1 6 2 12 3 18 4 24 x y 3 6 5 10 7 14 4 8 12

Is this a direct variation?
Course 2 Identifying DV Is this a direct variation?