Answer quadratic equation in the simplest surd form/ exact from. 5-2x-x^2=0
5-2x-x2=0x2+2x-5=0 (moving everything over to the other side)then using the quadratic formula (to use a whiteboard during interview)a=1, b=2, c=-5x=(-2 +/- √(2^2 - 4x1x-5))/(2x1)x=(-2 +/- √(4+20))/2x=(-2 +/- √(24))/2... √24= √4 x √6 = 2 x √6x=(-2 +/- 2√6)/2x=2(-1 +/- √6)/2 (2 in the numerator and denominator cancel each other out)x= -1 +/- √6 there are usually 2 answers for a quadratic equation. Here the two answers would be reached by adding or subtracting the √6 from -1.
SO
Related Maths GCSE answers
All answers ▸Many students do not understand the rules for when one can 'cancel' in regards to fractions
Prove that (2*a^2 + 7a + 3)/(a + 3) is an odd number for any positive integer number, a.
A family go into a shop, they buy three sandwiches and two packets of crisps. It costs them £9. Another family buy five sandwiches and six packets of crisps. It costs them £19. How much does two sandwiches and five packets of crisps cost?
Prove that (2n+3)^2-(2n-3)^2 is a multiple of 8 for positive integer values of n