Quick and explain! i am offering 15 points (its only worth 6) and brainliest answer

What is the gcf of 20c^3-5c^4+30c^6

Which statement best describes how to determine whether f(x) = x squared- x +8 is an even function ?

Match the following reasons with the statements given to create the proof. 1. do = ob, ao = oc sas 2. doc = aob given 3. triangle cod congruent to triangle aob vertical angles are equal. 4. 1 = 2, ab = dc if two sides = and ||, then a parallelogram. 5. ab||dc if alternate interior angles =, then lines parallel. 6. abcd is a parallelogram cpcte