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When do I use 'ser' or 'estar'?

Both 'SER' and 'ESTAR' translate as 'to be', but they have different meanings.
SER is used to describe states of permanance: Descriptions, Occupations, Characteristics, Time, Origin, and Relationship...

Answered by Flora B. • Spanish tutor

1489 Views

Express 4x/(x^2-9) - 2/(x+3) as a single fraction in its simplest form.

In order to add or subtract terms to/from each other, both of their denominators (the number on the bottom of the fraction) must be the same. In this case they are different, so the first step is to try a...

Answered by Alex E. • Maths tutor

3317 Views

Explain the basic Principles of Medical Ethics

Medical ethics is based on four main principles, which are important to remember when discussing through ethical scenarios. The principles are: Autonomy - this is the right of the patient to make their ow...

Answered by Elisa W. • Medical School Preparation tutor

1602 Views

The equation for the reaction of carbon and nickel dioxide is: NiO + C ----> CO + Ni Calculate the percentage atom economy of this reaction to produce nickel to 3 significant figures.

Using a periodic table, you can find that: Molecular mass of carbon: 12Molecular mass of nickel: 59Formula mass of nickel oxide: 75 (=59+16)
Mass of all the reactants = 12+75=87Mass of the product we...

Answered by Emma N. • Chemistry tutor

5094 Views

Complete the square for the following equation: 2x^2+6x-3=0

2x²+6x-3=0To begin, we need to make sure x² is by itself, meaning that we divide the whole equation by 2. So from here we get (2x²+6x-3=0) / 2 = x²+3x-3/2=0. No...

Answered by • Maths tutor

5956 Views