Question

Find point of contact if line 3x+4y+20=0 touches circel x2 + y2 =16

Answer 1

Answer:

point of contact is (x=> -36/15, y=> -16/5)

Step-by-step explanation:

given, 3x+4y+20=0

=> x = -(4y+20)/3    (A)

substituting in x² + y² = 16

(16y² + 400 +  160y)/9  + y² = 16

16y² + 400 +  160y + 9y² = 144

25y² + 160y + 256 = 0

(5y+16)² = 0

y = - 16/5

from (A) , x = -(-4x16/5 +20)/3 = -36/15