Please help me with this sorry if sideways if something is wrong let me know

Quick translate "x is 12 units from 20" into an equation. what are the values of x being described? if you can answer any of my other questions that'd be great too

Which triangle congruence postulate or theorem justifies my claim that the steps i made using construction paper and scissors produce an isosceles triangle? was it sss, sas, asa, aas, or hl?

Find the solution set of this inequality. enter your answer in interval notation using grouping symbols. |8x-4| ≤ 12