Quadratic equations

There are 39 NRICH Mathematical resources connected to Quadratic equations
Plus or Minus
problem

Plus or Minus

Age
16 to 18
Challenge level
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Make and prove a conjecture about the value of the product of the Fibonacci numbers $F_{n+1}F_{n-1}$.
Golden Eggs
problem

Golden Eggs

Age
16 to 18
Challenge level
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Find a connection between the shape of a special ellipse and an infinite string of nested square roots.
Golden Construction
problem

Golden Construction

Age
16 to 18
Challenge level
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Draw a square and an arc of a circle and construct the Golden rectangle. Find the value of the Golden Ratio.
Polar Flower
problem

Polar Flower

Age
16 to 18
Challenge level
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This polar equation is a quadratic. Plot the graph given by each factor to draw the flower.
Golden Fibs
problem

Golden Fibs

Age
16 to 18
Challenge level
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When is a Fibonacci sequence also a geometric sequence? When the ratio of successive terms is the golden ratio!
In Between
problem

In Between

Age
16 to 18
Challenge level
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Can you find the solution to this algebraic inequality?
Xtra
problem

Xtra

Age
14 to 18
Challenge level
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Find the sides of an equilateral triangle ABC where a trapezium BCPQ is drawn with BP=CQ=2 , PQ=1 and AP+AQ=sqrt7 . Note: there are 2 possible interpretations.
Halving the Triangle
problem

Halving the Triangle

Age
16 to 18
Challenge level
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Draw any triangle PQR. Find points A, B and C, one on each side of the triangle, such that the area of triangle ABC is a given fraction of the area of triangle PQR.
Pentakite
problem

Pentakite

Age
14 to 18
Challenge level
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Given a regular pentagon, can you find the distance between two non-adjacent vertices?
How Many Balls?
problem

How Many Balls?

Age
16 to 18
Challenge level
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A bag contains red and blue balls. You are told the probabilities of drawing certain combinations of balls. Find how many red and how many blue balls there are in the bag.