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What are "x" and "y" and why are they used?

The letters "x" and "y", or any other similar letter in an equation, are examples of unknown variables . What this means is that we don't know their value, and often the aim of the game i...
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Answered by Colm M. • Maths tutor
8780 Views

Explain, in terms of sub-atomic particles, why the mass number of a magnesium atom is 24.

On the periodic table, Magnesium has the symbol 12 Mg 24 , where 24 is the mass number and 12 is the atomic number. The atomic number is the number of protons found inside an atom, while the mass number tell...
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Answered by Matthew N. • Chemistry tutor
31631 Views

What is an enzyme?

An enzyme is a type of protein that catalyses reactions that occur in the body. In many cases they are essential in order to allow reactions to occur under physiological conditions. There are many different ...
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Answered by Rohin A. • Biology tutor
5167 Views

Rearrange the equation y=3x+2 to make x the subject.

The most important thing to remember about rearranging equations is that what you do to one side, you have to do to the other side as well to balance it. In the question above, to get rid of the 2 on the rig...
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Answered by Matthew N. • Maths tutor
80150 Views

How do I know whether to add or minus in Pythagoras's theorem?

Firstly it has to be a right angled trinagle. Even if it is an irregukar shape, draw a line in to make it a right angled triangle. When you have your right angled triangle remember it is ALWAYS + if it is th...
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Answered by Nehemie M. • Maths tutor
42743 Views