By eliminating y y\,y from the equations
y=x−4, y = x - 4, y=x−4, 2x2−xy=8, 2x^2 - xy = 8, 2x2−xy=8,show that
x2+4x−8=0. x^2 + 4x - 8 = 0. x2+4x−8=0.Hence, or otherwise, solve the simultaneous equations
y=x−4, y = x - 4, y=x−4, 2x2−xy=8, 2x^2 - xy = 8, 2x2−xy=8,giving your answers in the form a±b3a \pm b\sqrt{3}a±b3, where a a\,a and b b\,b are integers.
Practise Edexcel A Level Old Maths Algebra and Functions 1 with exam-style questions for A Level Old Maths. 19 questions, matched to the Edexcel A Level Old Maths (9371) specification and written in Unit exams C1, C2, C3 and C4 plus two applied units (e.g. S1 and M1) 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.