Find a point on the y-axis that is at the same distance from the points (−5,2)(-5, 2) and (9,−2)(9, -2).

Answer: The point on the yy -axis equidistant from (−5,2)(-5, 2) and (9,−2)(9, -2) is (0,−7)(0, -7).

Step-by-step solution

Step 1: Define the point on the y-axis

A point on the yy -axis always has its xx -coordinate equal to 0. Therefore, we can represent the required point as P(0, y).

Step 2: Set up the distance condition

The problem states that the point PP is equidistant from points A(−5,2)A(-5, 2) and B(9,−2)B(9, -2). This means the distance from PP to AA is equal to the distance from PP to BB.

Step 3: Apply the distance formula

To simplify calculations, we square both sides of the distance equality, PA=PBPA = PB, to remove the square roots. We then apply the distance formula, which states that the distance between two points (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2) is (x2−x1)2+(y2−y1)2\sqrt{(x_2 - x_1)^2 + (y_2 - y_1)^2}.

Step 4: Substitute the coordinates and simplify

Substitute the coordinates of P(0, y), A(−5,2)A(-5, 2), and B(9,−2)B(9, -2) into the squared distance formula. Then, simplify the squared terms and expand the binomials using the formula (a±b)2=a2±2ab+b2(a \pm b)^2 = a^2 \pm 2ab + b^2.

Step 5: Solve for y

First, combine the constant terms on both sides. Then, subtract y2y^2 from both sides. Collect the yy terms on one side and the constant terms on the other side. Finally, divide to find the value of yy.

Step 6: State the coordinates of the point

Since we found y=−7y = -7 and the point is on the yy -axis, its coordinates are (0,−7)(0, -7).

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