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A line with direction cosines proport...

A line with direction cosines proportional to `1,-5, a n d-2` meets lines `x=y+5=z+1a n dx+5=3y=2zdot` The coordinates of each of the points of the intersection are given by a. `(2,-3,1)` b. `(1,2,3)` c. `(0,5//3,5//2)` d. `(3,-2,2)`

A

(2,-3,1)

B

(1,2,3)

C

`(0,5//3,5//2)`

D

(3,-2,2)

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To solve the problem, we need to find the coordinates of the intersection of a line with direction cosines proportional to \(1, -5, -2\) and two given lines. ### Step 1: Understand the direction ratios The direction ratios of the line are proportional to \(1, -5, -2\). This means we can express the line in parametric form as: \[ x = x_1 + t, \quad y = y_1 - 5t, \quad z = z_1 - 2t \] where \((x_1, y_1, z_1)\) is a point on the line and \(t\) is a parameter. ### Step 2: Set up the equations for the given lines The first line is given in symmetric form: \[ x = y + 5 = z + 1 \] From this, we can derive the parametric equations: 1. \(x = y + 5\) 2. \(z = x - 1\) The second line is also given in symmetric form: \[ x + 5 = 3y = 2z \] From this, we can derive the parametric equations: 1. \(x = 3y - 5\) 2. \(z = \frac{x + 5}{2}\) ### Step 3: Express the intersection condition For the intersection, we need to find a common point \((x, y, z)\) that satisfies both lines. ### Step 4: Substitute the equations Substituting \(y\) from the first line into the second line: 1. From \(x = y + 5\), we have \(y = x - 5\). 2. Substitute \(y\) into \(x = 3y - 5\): \[ x = 3(x - 5) - 5 \] Simplifying this gives: \[ x = 3x - 15 - 5 \implies 2x = 20 \implies x = 10 \] ### Step 5: Find \(y\) and \(z\) Now, substituting \(x = 10\) back to find \(y\): \[ y = 10 - 5 = 5 \] Now substitute \(x\) into \(z = x - 1\): \[ z = 10 - 1 = 9 \] ### Step 6: Check if the point satisfies both lines Now we have the point \((10, 5, 9)\). We need to check if this point satisfies the second line: 1. Check \(x + 5 = 3y\): \[ 10 + 5 = 3(5) \implies 15 = 15 \quad \text{(True)} \] 2. Check \(2z = x + 5\): \[ 2(9) = 10 + 5 \implies 18 = 15 \quad \text{(False)} \] This means \((10, 5, 9)\) is not the intersection point. ### Step 7: Check given options Now we will check the given options one by one to see which one satisfies both lines. 1. **Option (2, -3, 1)**: - For the first line: \[ 2 = -3 + 5 \quad \text{(True)} \] \[ 1 = 2 - 1 \quad \text{(True)} \] - For the second line: \[ 2 + 5 = 3(-3) \quad \text{(False)} \] 2. **Option (1, 2, 3)**: - For the first line: \[ 1 = 2 + 5 \quad \text{(False)} \] 3. **Option (0, \frac{5}{3}, \frac{5}{2})**: - For the first line: \[ 0 = \frac{5}{3} + 5 \quad \text{(False)} \] 4. **Option (3, -2, 2)**: - For the first line: \[ 3 = -2 + 5 \quad \text{(True)} \] \[ 2 = 3 - 1 \quad \text{(True)} \] - For the second line: \[ 3 + 5 = 3(-2) \quad \text{(False)} \] ### Conclusion After checking all the options, we find that the only point that satisfies the first line is \((2, -3, 1)\) and \((1, 2, 3)\) satisfies the second line. Therefore, the coordinates of the intersection points are: - Option (a) \( (2, -3, 1) \) - Option (b) \( (1, 2, 3) \)

To solve the problem, we need to find the coordinates of the intersection of a line with direction cosines proportional to \(1, -5, -2\) and two given lines. ### Step 1: Understand the direction ratios The direction ratios of the line are proportional to \(1, -5, -2\). This means we can express the line in parametric form as: \[ x = x_1 + t, \quad y = y_1 - 5t, \quad z = z_1 - 2t \] where \((x_1, y_1, z_1)\) is a point on the line and \(t\) is a parameter. ...
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