Q. If y varies directly with x and y=14 when x=2, find y when x=1. Write and solve a direct variation equation to find the answer.y = ____
Select equation for direct variation: Select the equation that represents direct variation.Since y varies directly with x, we can use the direct variation equation: y=kx.
Substitute values into equation: We know that y=14 when x=2. Substitute the values into the direct variation equation y=kx. Plug in 2 for x and 14 for y in y=kx to find the constant of proportionalityk. 14=k×2
Solve for constant of proportionality: Solve for the constant of proportionality k.Divide both sides by 2 to isolate k.214=2(k×2)7=k
Write direct variation equation: Write the direct variation equation using the value of k.Since we found that k=7, the direct variation equation is y=7x.
Find y when x=1: Use the direct variation equation to find y when x=1. Substitute 1 for x in the equation y=7x. y=7×1y=7
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