Intenta pensarlo antes de mirar la solución.

Solución:
1) Hallemos primero el área del rectágulo verde, que está dividido en dos cuadrados cuyas diagonales son el radio de la semicircunferencia. Expresemos primero el lado en función del radio.

2) Hallemos ahora el área del cuadrado azul. Expresemos primero el lado del cuadrado en función del radio de la semicircunferencia.

Por tanto, el área de la figura verde es R² y el área de la figura azul es 4R²/5. Como 1>4/5, podemos concluir que el área de la figura verde es mayor que el de la figura azul.

What is algebra for?

ALGEBRA

Here there are some tools to develop this unit.

- Algebra (Flashcards- Theory)
- Vocabulary English-Spanish

PROPORTIONALITY

Some resources to develop this unit.

- Proportionality (Flashcards) (Theory)
- Vocabulary English-Spanish
- Activities

Pie Charts and Frequency Diagrams

Check your knowledge about pie charts and frequency diagrams!

http://www.bbc.co.uk/education/guides/zyr2pv4/test

Statistics (Estadística)

A brief sumary about statistics in second level of compulsary secondary school and some examples to develop this unit.

- Flash cards (Theory)
- Vocabulary
- Example 1: Qualitative data
- Example 2: Discrete quantitative data
- Example 3: Continuous quantitative data

FRACTIONS. PROPER AND IMPROPER FRACTIONS.

All together!
Here, you have the lyrics. LYRICS

FRACTIONS

Here you have some files to develop this topic.

- Fractions (Flash Cards)
- Fraction (Vocabulary)

St. Aloysius College (Holland)

Our friends from St. Aloysius College! Wow, what a wonderful place!

https://prezi.com/9ofgcejgzps7/st-aloysius-college/#

DECIMAL SYSTEM

Here you have some files to develop the unit "Decimal System".

• Decimal System (Flash cards)
• Vocabulary. Decimal System
• Activities. Decimal System

The order of operations. Game.

PLAY AND LEARN

http://www.math-play.com/Order-of-Operations-Millionaire/division-millionaire.html

Negative numbers. VIDEOS

Negative numbers: Where can you find them?



How do negative numbers work? (Operations)

DIVISIBILITY AND INTEGER NUMBERS

Hello everybody, we are going to start the new academic year. Here you have some interesting files to develop bilingual contents in 2ºESO.

- Divisibility and integer numbers (FLAHS CARDS)

- Vocabulary (English - Spanish)

- Activities

PI

It's quite a bit freaky but it's so funny! Enjoy and learn!

(2º ESO BIL) SIMILAR SHAPES

Extend your knowledge.

http://www.carmel.org.uk/elearning/similar_shapes/index.htm

(Select intermediate) 

(2º ESO BIL) Solving equations

VIDEO (EQUATIONS)

Can you help Garth to find his way through the "unknown" and get home safely in time for tea?

http://www.bbc.co.uk/schools/gcsebitesize/maths/algebra/equationsact.shtml

(2º ESO BIL) VIDEO

VIDEO (ALGEBRA)

The following videos show a little introducction about Algebra.


http://www.bbc.co.uk/schools/gcsebitesize/maths/algebra/symbolsact.shtml

http://www.bbc.co.uk/schools/gcsebitesize/maths/algebra/formulaeact.shtml

(2º ESO BIL) Exam (vocabulary)

Do the quiz that you can find in the following link. After that, write in "comentarios" your score with your name. Be honest. Good luck.

http://www.bbc.co.uk/apps/ifl/schools/gcsebitesize/maths/quizengine?quiz=percentagesfoundationtest&templateStyle=maths

(2º ESO) Proportionality (VIDEOS)

Ratios:
http://www.bbc.co.uk/schools/gcsebitesize/maths/number/ratiosact.shtml
Percentages:
http://www.bbc.co.uk/schools/gcsebitesize/maths/number/percentagesact.shtml

ORDENA FRACCIONES

Juego interactivo para ordenar fracciones:

http://www.sectormatematica.cl/flash/fracciones.swf