# Puzzles

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#### Sunday Afternoon Maths LXVII

Coloured weightsNot Roman numerals

#### Advent calendar 2018

#### Sunday Afternoon Maths LXVI

Cryptic crossnumber #2#### Sunday Afternoon Maths LXV

Cryptic crossnumber #1Breaking Chocolate

Square and cube endings

List of all puzzles

## Tags

probabilty rugby speed area grids angles time chalkdust crossnumber triangles cryptic clues star numbers logic folding tube maps digits money algebra integration numbers trigonometry chess mean factorials parabolas volume division doubling surds proportion 3d shapes shape dates regular shapes unit fractions factors scales odd numbers colouring prime numbers people maths number functions palindromes sums integers taxicab geometry square numbers polygons calculus bases percentages quadratics square roots remainders irreducible numbers squares graphs pascal's triangle crossnumbers multiplication sequences averages crosswords coordinates christmas multiples cards clocks planes dodecagons ellipses 2d shapes hexagons books menace cube numbers rectangles lines addition chocolate coins perimeter means circles advent games fractions probability sum to infinity perfect numbers cryptic crossnumbers shapes wordplay dice floors ave symmetry balancing sport indices geometry triangle numbers routes arrows partitions complex numbers spheres differentiation## Parabola

Source:

*Alex Through the Looking-Glass: How Life Reflects Numbers and Numbers Reflect Life*by Alex BellosOn a graph of \(y=x^2\), two lines are drawn at \(x=a\) and \(x=-b\) (for \(a,b>0\). The points where these lines intersect the parabola are connected.

What is the y-coordinate of the point where this line intersects the y-axis?

If you enjoyed this puzzle, check out Sunday Afternoon Maths XVIII,

puzzles about parabolas, or a random puzzle.

puzzles about parabolas, or a random puzzle.