Q. A direct variation includes the points (3,15) and (1,n). Find n. Write and solve a direct variation equation to find the answer.n=___
Select equation direct variation: Select the equation that represents direct variation.Since y varies directly with x, we use the direct variation equation: y=kx.
Find constant proportionality: Use the given point (3,15) to find the constant of proportionality(k). Substitute the values in y=kx. Plug in 3 for x and 15 for y in y=kx. 15=k×3
Solve constant proportionality: Solve for the constant of proportionality k.Divide both sides by 3 to isolate k.315=3(k×3)5=kk=5
Write direct variation equation: Write the direct variation equation using the value of k.Since k=5, the direct variation equation is y=5x.
Find n: Use the direct variation equation to find n when x=1. Substitute 1 for x in y=5x to find n. n=5×1n=5
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