Solve 5x^2 = 10x + 4 Give your answers to 2 decimal places. [4 marks]
5x^2 = 10x + 4 5x^2 - 10x = 4 5x^2 - 10x - 4 = 0 ax^2 +bx +c = 0 x = (-b (+/-) ( b2 -4ac)1/2) /(2a) x = (--10 (+/-) ((-10)2- (4 x 5 x -4))1/2)/(2 x 5) x = (10 (+/-) (100 + 80)1/2)/10 x = (10 (+/-) (180)1/2 )/10 x = 2.341(...) and –0.341(...) x= 2.34 and –0.34 (to 2.d.p)
JT
Related Maths GCSE answers
All answers ▸6x – 7 = 14 – x
The ratio 2 centimetres to 6 metres can be written in the form 1 : n. Find the value of n.
Solve this set of linear equation to find x and y: 1. 8x + 2y =48 2. 7x +3y =47
Natasha has two bags of fruit. both bags have the same number of fruit in total. 1/3rd of the fruit in bag 1 are apples and 15% of the fruit in bag 2 are apples. There are 20 apples in bag 1, how many apples are in bag 2?