SingaporeAccountingSyllabus dot point

Why must assets always equal liabilities plus owner's equity, and how does each transaction keep the equation balanced?

State and apply the accounting equation and show how transactions keep it in balance

A focused answer to the O-Level Principles of Accounts outcome on the accounting equation. The relationship between assets, liabilities and owner's equity, and how every transaction keeps the equation in balance through a dual effect.

Generated by Claude Opus 4.88 min answerUpdated 2026-06-06

Reviewed by: AI editorial process; not yet individually human-reviewed

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What this dot point is asking
The answer
Examples in context
Try this

What this dot point is asking

SEAB wants you to state the accounting equation and apply it: to show how every transaction changes the figures while keeping the two sides equal. The central insight is the dual effect - every transaction affects at least two items, and the changes always cancel out so that assets stay equal to liabilities plus owner's equity. This balance is the bedrock of double-entry book-keeping and of the statement of financial position.

The answer

The equation

The accounting equation states:

\text{Assets} = \text{Liabilities} + \text{Owner's Equity}

It says that everything the business owns (its assets) was funded either by amounts it owes to outsiders (liabilities) or by the owner's stake (equity). It can be rearranged:

\text{Owner's Equity} = \text{Assets} - \text{Liabilities}

Owner's equity is therefore the residual: what would be left for the owner if all assets were sold and all debts paid.

The dual effect

Every transaction has a dual effect - it changes at least two items by the same total, so the equation stays balanced. There are a few patterns:

Transaction type	Effect on the equation
One asset up, another asset down	Assets unchanged overall; equation still balances
Asset up, liability up	Both sides rise by the same amount
Asset up, equity up (capital or income)	Both sides rise by the same amount
Asset down, liability down	Both sides fall by the same amount
Asset down, equity down (drawings or expense)	Both sides fall by the same amount

How profit and drawings affect equity

Trading changes equity through profit, and the owner changes it through capital and drawings:

\text{Closing equity} = \text{Opening equity} + \text{Capital introduced} + \text{Profit} - \text{Drawings}

Income increases equity (and an asset); expenses decrease equity (and an asset or increase a liability). This is why the income statement, which finds profit, ultimately updates owner's equity in the statement of financial position.

Worked example

Show how each of the first four transactions of a new business affects the accounting equation, and confirm it balances after each. (1) Owner pays in $\$ 20,000 $cash. (2) Buys a van for$ \ $12\,000$ cash. (3) Buys goods for $\$ 3,000 $on credit. (4) Sells half those goods for$ \ $2\,500$ cash.

Step 1: Owner pays in capital

Cash (asset) up $\$ 20,000 $; owner's equity up$ \ $20\,000$ . Assets $\$ 20,000 = $liabilities$ \ $0 +$ equity $\$ 20,000$.

Step 2: Buy a van for cash

Van (asset) up $\$ 12,000 $; cash (asset) down$ \ $12\,000$ . Total assets unchanged at $\$ 20,000 $(van$ \ $12\,000$ + cash $\$ 8,000$). Still balances.

Step 3: Buy goods on credit

Inventory (asset) up $\$ 3,000 $; payables (liability) up$ \ $3\,000$ . Assets $\$ 23,000 = $liabilities$ \ $3\,000 +$ equity $\$ 20,000$.

Step 4: Sell half the goods for cash

Cash (asset) up $\$ 2,500 $; inventory (asset) down$ \ $1\,500$ (half of $\$ 3,000 $). Net assets up$ \ $1\,000$ , which is the profit, so equity up $\$ 1,000$.

Item	After step 4
Cash $(8\,000 + 2\,500)$	10,500
Van	12,000
Inventory $(3\,000 - 1\,500)$	1,500
Total assets	24,000
Payables	3,000
Equity $(20\,000 + 1\,000)$	21,000
Liabilities + equity	24,000

Assets $\$ 24,000 = $liabilities$ \ $3\,000 +$ equity $\$ 21,000$. The equation holds after every step.

Examples in context

Example 1. Borrowing to buy equipment. A workshop borrows $\$ 15,000 $from a bank and immediately spends it on a machine. Cash rises then falls, the machine (asset) rises$ \ $15\,000$ , and the loan (liability) rises $\$ 15,000 $. Assets and liabilities both rise by$ \ $15\,000$ while equity is untouched, because borrowing does not make the owner richer - it just funds an asset.

Example 2. A year of trading. A trader starts the year with equity of $\$ 40,000 $, makes a profit of$ \ $18\,000$ , introduces no new capital, and takes $\$ 12,000 $of drawings. Closing equity$ = 40,000 + 18,000 - 12,000 = \ $46\,000$ . This single line shows how the income statement (profit) and the owner's withdrawals together drive the change in equity reported on the statement of financial position.

Try this

Q1. A business has assets of $\$ 60,000 $and owner's equity of$ \ $35\,000$ . State its liabilities. [1 mark]

Cue. Liabilities $= \text{assets} - \text{equity} = 60\,000 - 35\,000 = \$ 25,000$.

Q2. State the effect on the accounting equation of buying inventory for $\$ 4,000$ on credit. [2 marks]

Cue. Inventory (asset) up $\$ 4,000 $and payables (liability) up$ \ $4\,000$ ; both sides rise by $\$ 4,000$ and the equation still balances.

Q3. Opening equity is $\$ 50,000 $. During the year the owner introduces$ \ $10\,000$ , the business makes a $\$ 22,000 $profit, and drawings are$ \ $15\,000$ . Find the closing equity. [3 marks]

Cue. Closing equity $= 50\,000 + 10\,000 + 22\,000 - 15\,000 = \$ 67,000$.

Exam-style practice questions

Practice questions written in the style of SEAB exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.

Original6 marksA business has assets of

\

45\,000

and liabilities of

18\,000

. (a) Calculate the owner's equity. The owner then introduces a further

\

5\,000

cash and the business buys equipment for

8\,000

on credit. (b) State the new figures for assets, liabilities and owner's equity, and show the equation still balances.

Show worked answer →

(a) Owner's equity $= \text{assets} - \text{liabilities} = 45\,000 - 18\,000 = \$ 27,000$.

(b) Effect of each event:

Owner pays in $\$ 5,000 $cash: assets up$ \ $5\,000$ , owner's equity up $\$ 5,000$.
Buy equipment $\$ 8,000 $on credit: assets up$ \ $8\,000$ , liabilities up $\$ 8,000$.

Item	Start	Change	End
Assets	45,000	+5,000 +8,000	58,000
Liabilities	18,000	+8,000	26,000
Owner's equity	27,000	+5,000	32,000

Check: assets $\$ 58,000 = $liabilities$ \ $26\,000 +$ owner's equity $\$ 32,000$. The equation balances.

Markers reward the $\$ 27,000$ equity, the correct dual effect of each event, and a clear demonstration that assets equal liabilities plus equity at the end.

Original5 marksState the effect of each transaction on assets, liabilities and owner's equity: (a) the business pays a supplier

\

2\,000

by cheque; (b) the business makes a cash sale of

900

on goods that cost

\

600

; (c) the owner takes

400

cash as drawings.

Show worked answer →

(a) Pay supplier $\$ 2,000 $by cheque: an asset (bank) falls$ \ $2\,000$ and a liability (payable) falls $\$ 2,000$. Owner's equity is unchanged.

(b) Cash sale of $\$ 900 $on goods costing$ \ $600$ : cash (asset) rises $\$ 900 $, inventory (asset) falls$ \ $600$ , so net assets rise $\$ 300 $; owner's equity rises$ \ $300$ through the $\$ 300 $profit. Total assets rise$ \ $300$ .

Markers reward the correct direction and amount of change for each element, and recognising that the $\$ 300$ profit in (b) increases equity while (a) leaves equity unchanged.