solve 2x^2+4x-7=0
Notice that this is a quadratic. First you should try factorisation, then if unsuccessful try completing the square (or the quadratic formula). In this example, factorisation is not possible (I can this further with demonstration.) So we must try Completing the square. Since the x^2 term has a '2' in front of it, we must get rid of this first, by taking it out as a factor. Then follow the give procedure for completing the square (I can show this further using the white board). If the student struggles with this approach I would consider letting them just use the quadratic formula - this would be a good way to check too.
KW
Related Maths GCSE answers
All answers ▸f(x) = 3x - 2a || g(x) = 2ax + 1 || fg(x) = 2x + b/2
solve the Simultaneous equations: y= x+6 and y=2x^23
There are only red , blue and purple counters in a bag. The ratio of the number of red counters to the number of blue counters is 3 : 17. If a counter is taken randomly the probability that it is purple is 0.2 Work out the probability for it to be red.
From factorising a^2-b^2 hence or otherwise simplify fully (x^2 + 4)^2 - (x^2-2)^2