Find the ratio in which the line segment joining A(1, -5) and B(-4, 5) is divided by the x-axis, and find the coordinates of the point of division.

Answer: The ratio is 1:11:1 and the coordinates of the point of division are (−32,0)(-\frac{3}{2}, 0).

Step-by-step solution

Step 1: Define the point of division and ratio

Since the point lies on the xx -axis, its yy -coordinate must be 0. We assume the ratio in which the line segment is divided is k:1k:1. This simplifies calculations compared to m1:m2m_1:m_2.

Step 2: Apply the section formula for y-coordinate

We use the section formula for the yy -coordinate. Here, (x1,y1)=(1,−5)(x_1, y_1) = (1, -5) and (x2,y2)=(−4,5)(x_2, y_2) = (-4, 5). The yy -coordinate of the point of division PP is 0.

Step 3: Solve for the ratio k

Substitute the known values into the section formula for yy. Since y=0y=0, we can solve the equation 0=5k−5k+10 = \frac{5k - 5}{k+1} for kk. This gives 5k−5=05k - 5 = 0, which simplifies to k=1k=1.

Step 4: State the ratio

Since k=1k=1, the ratio k:1k:1 becomes 1:11:1. This means the xx -axis divides the line segment AB in the ratio 1:11:1, implying it is the midpoint.

Step 5: Apply the section formula for x-coordinate

Now we use the section formula for the xx -coordinate with k=1k=1. Here, (x1,y1)=(1,−5)(x_1, y_1) = (1, -5) and (x2,y2)=(−4,5)(x_2, y_2) = (-4, 5).

Step 6: Solve for x and state the coordinates

Substitute k=1k=1 and the xx -coordinates into the formula to find xx. The coordinates of the point of division are (x,0)(x, 0), which is (−32,0)(-\frac{3}{2}, 0).

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