A trapezoid is isosceles if and only if
(1) The base angles are congruent
(2) The diagonals are congruent
(3) The opposite angles are supplementary
So the description does not guarantee that a trapezoid is isoceles for "Congruent bases".
It will be 5 cm and use 3.14 to multiply
1. distribute a 1 to the 12 and 8a
2. you'll get 15+ 12 +8a
3. add the like terms(15 and 12)
4. your final answer will be 27+8a
210 divided by 12 is 17.5 so u]your answer is 17.5
