Circles Γ1 and Γ2 intersect at 2 distinct points A and B. A line l through A intersects Γ1 and Γ2 at C and D, respectively. Let M be the midpoint of CD. The line MB intersects Γ1 and Γ2 again at E and F, respectively. If MA=129,MB=156 and MC=182, what is the value of EF?

29*182 = ME*156, so ME = 33.8333

MD = MC = 129+182 = 311
MF*156 = 129*311, so MF = 257.173
EF = MF+ME = 33.833+257.173 = 291

To find the value of EF, we can use the Power of a Point theorem.

1. Start by drawing a diagram to visualize the given information.
Draw Circles Γ1 and Γ2 intersecting at points A and B. Draw line l passing through A and intersecting Γ1 at C and Γ2 at D.
Draw line MB intersecting Γ1 at E and Γ2 at F. Also, label MA = 129, MB = 156, and MC = 182.

2. We can observe that MA and MC are both secants of Circle Γ1, so we can use the Power of a Point theorem to find the value of MC.
According to the Power of a Point theorem, the product of the lengths of the secant segments of a circle intersecting outside the circle is equal.
Therefore, MA * MC = MB * ME
Substitute the given values: 129 * 182 = 156 * ME
Solve for ME:
ME = (129 * 182) / 156
ME ≈ 150.23

3. Now, we can find the value of MF using a similar approach. Since MB and MC are both secants of Circle Γ2, we have:
MB * ME = MF * MD
Substitute the given values: 156 * 150.23 = MF * MD
Solve for MF:
MF = (156 * 150.23) / MD

4. To proceed, we need to find the value of MD. Since MD is a secant of Circle Γ2, we can use the Power of a Point theorem again.
MA * MC = MD * ME
Substitute the given values: 129 * 182 = MD * 150.23
Solve for MD:
MD = (129 * 182) / 150.23

5. Substitute the value of MD back into the equation for MF:
MF = (156 * 150.23) / MD

6. Finally, we need to find the length of EF. Since EF is a secant of both circles, we can use the Power of a Point theorem:
MF * MD = ME * MC
Substitute the values:
(156 * 150.23) / MD * MD = ME * 182
Solve for ME:
EF = (156 * 150.23 * 182) / (MD * MD)
Substitute the value of MD from step 4 and calculate EF.