Find a point on the yy -axis which is equidistant from the points A(6,5)A(6, 5) and B(−4,3)B(-4, 3).

Answer: The point on the yy -axis equidistant from A(6,5)A(6, 5) and B(−4,3)B(-4, 3) is (0,9)(0, 9).

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. So, we can represent the required point as P(0,y)P(0, y).

Step 2: Set up the distance condition

The problem states that the point PP is equidistant from points A(6,5)A(6, 5) and B(−4,3)B(-4, 3). 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 into the formula

Substitute the coordinates of P(0,y)P(0, y), A(6,5)A(6, 5), and B(−4,3)B(-4, 3) into the squared distance formula. For PA2PA^2, we use x1=0,y1=yx_1=0, y_1=y and x2=6,y2=5x_2=6, y_2=5. For PB2PB^2, we use x3=0,y3=yx_3=0, y_3=y and x4=−4,y4=3x_4=-4, y_4=3.

Step 5: Simplify and expand the equation

First, calculate the squared terms for the xx -coordinates: (−6)2=36(-6)^2 = 36 and (4)2=16(4)^2 = 16. Then, expand the squared binomials using the formula (a−b)2=a2−2ab+b2(a-b)^2 = a^2 - 2ab + b^2: (y−5)2=y2−10y+25(y-5)^2 = y^2 - 10y + 25 and (y−3)2=y2−6y+9(y-3)^2 = y^2 - 6y + 9.

Step 6: Combine constant terms and variables

Combine the constant terms on both sides of the equation. On the left side, 36+25=6136 + 25 = 61. On the right side, 16+9=2516 + 9 = 25.

Step 7: Solve for y

Subtract y2y^2 from both sides of the equation. Then, isolate the terms containing yy on one side and the constant terms on the other side. Perform the arithmetic to find the value of yy.

Step 8: State the coordinates of the point

Since we found y=9y = 9 and the point is on the yy -axis, its coordinates are (0,9)(0, 9).

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