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To expand the brackets you need to multiply each item inside with the number on the outside. The first bracket is expanded as follows: 5x = 5x, 53 = 15, therefore 5x + 15. There is a minus sign i...

example: solve the simultaneous equations 3x+2y=4 and 2x+y=3

1:   3x+2y=4
2:   2x+y=3

want to either get same number of x's or same number of y's in equa...

This is a simple yet standard GCSE question, especially in non-calculator papers. The solution is simple: if the student is picked at random, then the probability 2/5 must represent a ratio where the othe...

Firstly we need to work out the new price of the 3 litres of shampoo after 15% has been taken off.  Let's use the three step method for percentages. 100% is £12.80 £12.80/ 100= £0.128     1% is £0.128 £0....