Answer:
Step-by-step explanation:
From Federalist No. 10:
"Liberty is to be found only in a society of laws and not of men. ...If a majority be united by a common interest, the rights of the minority will be insecure...To secure the public good and private rights against the danger of such a faction, and at the same time preserve the spirit and the form of popular government, is then the great object to which our inquiries are directed..."
Here, Madison argues that checks and balances are needed to prevent the "tyranny of the majority" and protect the rights and interests of minorities. Factions must be controlled to secure liberty and the public good.
From Federalist No. 51:
"In a word, as liberty can have nothing to fear from the judiciary alone, but would have every thing to fear from its union with either of the other departments; that as all the effects of such a union must ensue from a dependence of the former on the latter, notwithstanding a nominal and apparent separation; that as, from the natural feebleness of the judiciary, it is in continual jeopardy of being over-awed, and forced to an exercise of its functions in subservience to the legislative or executive will; and, finally, that all the conventional checks upon the legislature will not form an effectual barrier against its encroachments, - it is far more rational to conclude, that a accusations made against a single branch of the Government, would rarely be, if ever, justified."
Here, Hamilton argues that separation of powers with checks and balances is necessary to prevent any one branch from having too much control or "tyranny". No branch alone can threaten liberty, but together they could undermine it, thus checks are needed to maintain separation and balance of power.
In summary, the key benefits of separation of powers with checks and balances are:
Prevents "tyranny of the majority" by protecting minority rights. No single faction controls government power.
Prevents consolidation of power in one branch. Power remains balanced and separated.
Secures liberty by making oppression difficult. Tyranny would require cooperation of multiple branches against their own self-interest.
Upholds the system of American republican self-government. Checks and balances are integral to the Constitution's design.