Video Transcript
If π¦ varies directly with π₯ and π¦ equals 14 when π₯ equals six, determine the constant of proportionality.
A direct variation is a relationship in which the ratio of π¦ to π₯ is a constant π. We say π¦ varies directly with π₯, so this constant of proportionality that we need to find is π.
And it says to find it when π¦ is equal to 14 and π₯ is equal to six, so letβs put those in. So we replaced π¦ with 14 and π₯ with six. So to solve for π, we need to divide both sides by six. The sixes cancel on the right-hand side.
Fourteen-sixths is equal to π, but fourteen-sixths reduces. Since two goes into 14 and six, π will be equal to seven-thirds, because two goes into 14 seven times and two goes into six three times.