For a), this is clearly a given as it is literally to the right of where it says “Given:” For b), since ON bisects ∠JOH, this means that it splits it into two separate angles - JON and HON, which are similar due to that bisects mean that it splits it equally into two halves For c), since NO is the same thing as NO, it is equal to itself For d), since AAS (angle-angle-side) congruence states that if there are two angles that are congruent (proved in a) and b) ) as well as that a side is congruent (proved in c) ), two triangles are congruent For e), since two triangles are congruent, every side must have one side that it matches up to in the other triangle. As the opposite side of angle H is JO and the opposite side of angle J is OH, and ∠J=∠H, those two are congruent. As JN and HN are the two sides left, they must be congruent.
He already had 100 into the account so we add that, 25x is derived from the fact that x=the amount of months and 25 is the amount per a month he saves.
2/4 and 4/8 are equivalent because you can use the butterfly method of multiplication. Meaning you multiply the numerator by the other fractions denominator and vis-versa.
