+1005 My gut tells me that AD is 3*2 = 6...
So 2(3+3+4+5) = 2*15 = 30
Cphill probably meant AD is 2*4
+128407 Yeah....that's a little confusing
Note that if angle B = angle D, than the tangents drawn from D have the same length as the tangents drawn from B
The tangents from B both have the length of 4 cm
So....the two tangents drawn from D have the same length
And the tangents drawn from A = 3cm
And the tangents drawn from C = 5cm
So
[ tangents drawn from B + tangents drawn from D + tangents drawn from A + tangents drawn from C] =
[ (4 + 4) + (4 + 4) + (3 + 3) +(5 + 5) ] =
[ 8 + 8 + 6 + 10] =
32 cm
+1005 Also it appears that the radius(based on image) is 4.5 since 4 and 5 seem to be equally above/below it.
In that case the diameter is 9.
Hmm.
+128407 Consider this, hugo
[ Remember that tangents drawn to a circle from an exterior point have equal lemgths ]
If we draw radii to the midpoints of AD . DC, AB,BC we will create congruent quadrilaterals
Therefore....the midpoint of BC to B = 4
And this is a tangent
And the midpoint of AB to B is a tangent with the same length
But since we have congruent quadrilaterals then the tangents drawn from D to the circle will have the same length as those drawn from B to the circle = 4
And the tangents drawn from A have the same length = 3
And the tangents drawn from C have the same length = 5
So...the perimeter is just 2 [ 4 + 4 + 5 + 3] = 32 cm
