Given that the length of the line L is 5 when it passes through P (3,1) and is cut by two parallel lines l1x + y + 1 = 0l2x + y + 6 = 0, the equation of L is obtained Find out the angle between L and L1, L2 as α = 45 degrees, then know KL is 1, and then calculate it in oblique form. Why is my answer wrong

Given that the length of the line L is 5 when it passes through P (3,1) and is cut by two parallel lines l1x + y + 1 = 0l2x + y + 6 = 0, the equation of L is obtained Find out the angle between L and L1, L2 as α = 45 degrees, then know KL is 1, and then calculate it in oblique form. Why is my answer wrong

In the past, doing this problem is similar to eating spinach, but now I don't know it's OK, but the idea is absolutely no problem. I used to be very good at mathematics. I can do this kind of problem by setting a * x + b * y + C = 0. This is a general formula, which can prevent the omission of some special equations. Then I can substitute the point P, and then according to the length of line L1 and L2, I can get

Find the equation of the circle passing through point m (3, - 1) and tangent to point n (1,2) with circle C: x2 + Y2 + 2x-6y + 5 = 0

Let the equation of circle be: (x-a) 2 + (y-b) 2 = R2, the center of circle be known: (- 1, 3), radius be 5, from the meaning of the question, we can get: (3-A) 2 + (- 1-B) 2 = R2, (A-1) 2 + (b-2) 2 = R2, (a + 1) 2 + (B-3) 2 = (5 + R) 2, the solution is a = 207, B = 1514, R2 = 845196