Q. If y varies directly with x and y=15 when x=5, find y when x=1. Write and solve a direct variation equation to find the answer.y = ____
Establish direct variation equation: Establish the direct variation equation.Since y varies directly with x, the equation can be written as y=kx, where k is the constant of proportionality.
Find constant k: Use the given values to find the constant k. We know that y=15 when x=5. Substituting these values into the equation gives us 15=k×5.
Solve for k: Solve for k.Divide both sides of the equation by 5 to isolate k.515=5k×5k=3
Write equation with k: Write the direct variation equation with the found value of k. Now that we know k=3, the direct variation equation is y=3x.
Find y for x=1: Find y when x=1. Substitute x=1 into the direct variation equation y=3x. y=3×1y=3
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