Solve 5x^2 - 9x + 4 = 0 using the quadratic formula

The quadratic formula is (-b±sqrt(b^2-4ac))/2a where a is the coefficient of the x^2 term, b is the coefficient of the x term and c is the number. So, in this case a=5, b=-9 and c=4. Substitute this into the formula to get (9±sqrt(9^2-4x5x4))/2x5. This simplifies to (9+1)/10 and (9-1)/10 which gives x= 1 or 0.8.

MP

Related Maths GCSE answers

All answers ▸

A box contains 7 caramel doughnuts. They have masses of 56 g, 67 g, 45 g, 56 g, 58 g, 49 g and 50 g. Find the median, mean and mode values of these masses. Bonus: What mass of doughnut could be added to the box to make the mean mass = 61 g.


Solve the simultaneous equations: 1) 6a+b=11 , 2) 5a-2b=19


Expand and simplify: (2x+3)(x-8)


Expand the following: (4x+7)(7x-2)