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Describe how ionic and covalent bonding forms compounds (6). You may use diagrams to help.

Compounds are structures where two or more elements are chemically bonded together. These chemical bonds are ionic, covalent or metallic depending on the elements involved. Ionic bonds, form between a met...

Answered by Anthony H. • Chemistry tutor

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Jo wants to work out the solutions of x^2 + 3x – 5 = 0 She says, ‘‘The solutions cannot be worked out because x^2 + 3x – 5 does not factorise to (x + a)(x + b) where a and b are integers.’’ Is Jo correct?

She is not correct. We can solve a quadratic equation in other ways. The easiest way is to use the formula for quadratic equations.x = (-b +/- sq. root (b^2 - 4ac) / 2ax = -3 +/- sq. root 3^2 - 4x -5 / 2 ...

Answered by Kirsty A. • Maths tutor

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The range of a set of numbers is 15 1/4. The smallest number is –2 7/8. Work out the largest number.

First we need to understand what the range is. It is the difference between the smallest and largest numbers in a sample or list or numbers. If we add the range on to the smallest number we get the larges...

Answered by Kirsty A. • Maths tutor

11109 Views

Calculate the value of x

Angle AOB = 2x + 28. An angle at the circumference is half that at the centre, so angle ACB = x + 14. Opposite angles of a cyclic quadrilateral sum 180° , so ACB + ADB = 180. ADB is given as 3x - 70. This...

Answered by Eleanor L. • Maths tutor

5645 Views

What is excess supply?

Excess supply is a form of allocative inefficiency where the supply of a good or service becomes greater than the demand for this good or service in the market. This often happens because the price for a ...

Answered by Chenab B. • Economics tutor

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