Search over 10,000 free study notes

using the method, what two numbers multiply to create -1 and add to make 0 -1 must be 1 x -1 therefore answer is (x+1)(x-1) - is it clear how the single x value is cancelled out? x^2 +x -1 -x = x^2 -1

Solving by elimination

1. multiply the equations by a number so that the number in front of either x or y is the same for both equations:

3x + 4y = 10 (X2) --> 6x ...

The first thing to do in this problem is to expand the brackets. This means we times whatever is in the bracket by the number on the outside, in this instance the number is 3. We do not worry about the ri...

When dividing by a fraction, it is actually a multiplication. All you need to do is flip the second fraction over. This is known as the reciprocal. In this example the fraction we want to flip is 7/12. Fl...

1/2n² + 1/2n + 1

This is a hard one and maybe closer to a maths challenge question. It is easier to explain in person.

First common difference is 1 then 2 then 3 ...