2017 NCEA L2 Algebra

Simplify, leaving your answer with positive indices:

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Simplify, leaving your answer with positive indices.

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b) Fully simplify the expression

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Answer explanation

Factorising either the numerator or denominator got the Achieved mark.

Correct answer = Merit

David has mounted a square photo on a square piece of card as is shown.

The border around the photo is of constant width.

The photo has sides of length (n – 2) cm while the card has sides of (2n + 6) cm.

If the total area of the border is 200 square cm, find the width of the border.

(Round to 1 d.p. units not required)

Mathematical Equivalence

ON

Answer explanation

Set up the Quadratic or find expression for width in terms of n for Achieved.

Find two Solutions for Merit.

Find Width for Excellence

A teacher has hired a school bus for $560 for a day trip with students. The cost of hiring the bus is to be shared equally between the students. At the last moment, three of the students were unable to go. As a result, the cost to each of those who did go was increased by $1.50. How many students finally went on the trip?

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Answer explanation

A: Sets up Equation

M: Forms Quadratic

E: Solves

Solve the following equation for x:

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Answer explanation

Solve this equation for x:

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Evaluate

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(d) A computer depreciates continuously in value from $4699 to $1500 over a period of 4.25 years. The value, $y, of the computer t years after its value was $4699 can be modelled by a function of the form shown in the image, where r is a constant. Find the computer’s value after six years.

(Round to 2dp, units not required)

Mathematical Equivalence

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Answer explanation

A: Setup Equation

M: Find r

E: Solve

(e) Make a the subject of the formula:

Mathematical Equivalence

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