How to Find the Point on the Line y = 5x + 2 Closest to the Origin?

To find the point on the line y = 5x + 2 that is closest to the origin (0, 0), we can use the concept of distance from a point to a line.

The distance D from a point (x, y) to the origin is given by:

D = √(x² + y²)

However, since we want to minimize the distance, we can minimize the square of the distance to avoid dealing with the square root:

D² = x² + y²

Substituting the equation of the line into our distance formula, we have:

D² = x² + (5x + 2)²

Now, expand the equation:

D² = x² + (25x² + 20x + 4)

D² = 26x² + 20x + 4

To find the minimum distance, we can take the derivative of D² with respect to x and set it to zero:

d(D²)/dx = 52x + 20 = 0

Solve for x:

52x = -20

x = -20/52 = -5/13

Now, plug x back into the line equation to find y:

y = 5(-5/13) + 2

y = -25/13 + 2 = -25/13 + 26/13 = 1/13

Thus, the point on the line y = 5x + 2 that is closest to the origin is:

(-5/13, 1/13)

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