Answer:
22
Step-by-step explanation:
We are given the expression:—

When n = 5, substitute/change n to 5:—

Evaluate:—

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<u>Summary</u>
<u>Substitution</u>
Changing or replacing from a term to another terms/expression is called substitution.
Examples:—
If we are given the expression
and we want to find the value when y = 4, simply replace y-term to 4.

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If you have any doubts regarding my answer/explanation, do not hesitate to ask in comment!
Step-by-step explanation:
We have y = 13 - 3x and y = 7 - x.
=> 13 - 3x = 7 - x
=> 2x = 6, x = 3.
Then y = 7 - (3), y = 4.
Hence the price of a pencil is $3 and the price of a notebook is $4. (C)
Answer:
48 m²
If AB is 4 m and BC is 12 m then AD 12 m and you multiply 4 × 12 in it is 48 m²
Answer:
b
Step-by-step explanation: