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How do I solve a quadratic equation by factorising?

A quadratic equation is one that includes x 2 as the highest power of x. Factorising is achieved in 3 steps. Let’s consider the example x 2 -3x-3=1 1) Put the equation into the form ax 2 +bx+c=0 x 2 -3x-4=02...
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Answered by Shannon G. • Maths tutor
5649 Views

How do I expand brackets by multiplication?

It's worth remembering FOIL: First, Outside, Inside, Last.Say we have the following: (a+b)(c+d), where a,b,c and d are positive integers. Using FOIL, we have: (First) + (Outside) + (Inside) + (Last) ac + ad ...
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Answered by Liam D. • Maths tutor
7465 Views

What is the cosine rule?

What is it? The cosine rule is a tool to find the size of an angle or the length of a side in a triangle. When to use it? - When we are given 2 sides and an angle- When we are given 3 sides How? For a triang...
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Answered by Naomi G. • Maths tutor
5779 Views

How do I use Pythagorus' Theorum?

Pythagorus' Theorum is used to calculate the lengths of the sides of a right angled triange, and is written mathematically as follows: a 2 + b 2 = c 2 The letters (a, b and c) each stand for one of the three...
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Answered by Narissa P. • Maths tutor
7255 Views

What can I say about the roots of a quadratic equation without actually calculating them?

If a quadratic equation is of the form ax 2 +bx+c, calculate D (Discriminant) whose value is b 2 -4ac. If the value of D is negative, the equation has imaginary roots. If the value of D is positive, the equa...
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Answered by Swapnil S. • Maths tutor
5123 Views