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Points A and B have coordinates (-5, 16) and (3,12) respectively.

C is the point that lies of the way along AB. Find the coordinates of C.

User Skme
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3 votes
Answer:

the coordinates of point C are approximately (0.56, 17.72)

Step by step Explanation:

To find the coordinates of point C, we need to find its distance from point A as a fraction of the distance between points A and B, and then use that fraction to find the coordinates of C.

Let's call the distance between points A and B "d". We can find the distance using the distance formula:

d = √[(x₂ - x₁)² + (y₂ - y₁)²]

where (x₁, y₁) and (x₂, y₂) are the coordinates of points A and B, respectively. Plugging in the values, we get:

d = √[(3 - (-5))² + (12 - 16)²] = √64 + 16 = √80

Now, let's call the fraction of the distance from A to B that C lies on "f". We know that C is closer to A than to B, so 0 ≤ f ≤ 1. We can find f using the formula:

f = AC/AB

where AC is the distance from A to C. We can use the distance formula again to find AC:

AC = √[(x - (-5))² + (y - 16)²]

where (x, y) are the coordinates of point C. We also know that C is on the line segment AB, so its x-coordinate must satisfy:

(x - (-5))/(3 - (-5)) = f

Simplifying, we get:

(x + 5)/8 = f

Solving for x, we get:

x = 8f - 5

Similarly, we can use the y-coordinate of C to form another equation:

(y - 16)/(12 - 16) = f

Simplifying and solving for y, we get:

y = 4(1 - f) + 16 = 20 - 4f

Now we have expressions for x and y in terms of f. We can substitute these into the expression for AC:

AC = √[(8f - 5 - (-5))² + (20 - 4f - 16)²] = √[64f² - 64f + 100]

Finally, we can plug in our expressions for AC and AB to solve for f:

f = AC/AB = √[64f² - 64f + 100]/√80

Squaring both sides and simplifying, we get a quadratic equation:

64f² - 64f + 100 = 80f²

16f² + 64f - 100 = 0

Dividing both sides by 4 and using the quadratic formula, we get:

f = (-64 ± √(64² - 4(16)(-100))) / 2(16)

f ≈ -0.32 or f ≈ 1.57

Since 0 ≤ f ≤ 1, the valid solution is:

f ≈ 0.57

Now we can use this value to find the coordinates of C:

x = 8f - 5 ≈ 0.56

y = 20 - 4f ≈ 17.72

Therefore, the coordinates of point C are approximately (0.56, 17.72)
User Peter Jurkovic
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