a=8a = 8a=8 b=−5b = -5b=−5 c=2c = 2c=2
Work out the value of b2−4acb^2 - 4acb2−4ac
Practise Edexcel IGCSE Maths Substitution with exam-style questions for IGCSE Maths. 27 questions, matched to the Edexcel IGCSE Maths (4MA1) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.