In isosceles triangle ∆abc, bm is the median to the base ac . point d is on bm . prove the following triangle congruencies: ∆amd ≅ ∆cmd.

See explanation

Step-by-step explanation:

In isosceles triangle ∆ABC, BM is the median to the base AC.

Since ΔABC is isosceles, then AB ≅ BC.

Since BM is the median, then AM ≅ MC.

Consider triangles ABM and CBM. In these triangles,

So, ΔABM ≅ ΔCBM by SSS postulate. Congruent triangles have conguent corresponding sides and angles, so

∠AMB ≅ ∠CMB.

Consider triangles AMD and CMD. In these triangles,

so ΔAMD ≅ ΔCMD by SAS postulate

answer: 25.4 units

step-by-step explanation: radius = 12.7 units

diameter = twice the radius

diameter = 12.7 x 2

= 25.4