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Factorise 3x^2 + 15x

To factorise an equation you need to look for factors that all the elements of the equation (3x^2 and 15x) have in common. You can do this all at one or in steps, to start with you can see that both parts ha...
EF
Answered by Eve F. • Maths tutor
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Discuss some of the limitations of the use of tidal energy.

One of the limitations include cost, of setup, installation and maintenance. But more sublty there are undetermined envronmental implications, and issues with the energy storage and distribution due to the f...
HW
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A curve has parametric equations x=t(t-1), y=4t/(1-t). The point S on the curve has parameter t=-1. Show that the tangent to the curve at S has equation x+3y+4=0.

To anwser this question we need to find a linear equation of the form y=mx+c which we can rearrange to give the desired equation. Firstly, we must find the gradient at the point S given by dy/dx. Using the p...
MF
Answered by Marcus F. • Maths tutor
8398 Views

Explain one negative externality that could occur due to the building of a new airport (2 marks)

This question tests the student's knowledge on the topic of negative externalities while also inviting them to think of its application in the real world. The buiding of a new airport is a common theme in Ec...
EA
6679 Views

A "day return" train ticket is £6.45. A "monthly saver" is £98.50. Sue worked for 18 days last month. She bought a day return ticket each day she worked. A monthly saver ticket is cheaper than 18 day return tickets. How much cheaper?

This is a simple GCSE question which might feature at the beginning of the paper. It tests the student's attention to detail by asking to find the DIFFERENCE and not just the price that Sue paid. Also, given...
EA
Answered by Ecaterina A. • Maths tutor
6106 Views