How to expand double brackets?

Use the FOIL method, first, outside, inside, last. 1) F: The first term in the first bracket multiplies the first term in the second bracket. 2) O: The first term in the first bracket jumps outside to multiply the second term in the second bracket. 3) I: The second term in the first bracket multiplies the first term in the second bracket so the two 'inside' terms are multiplying together 4) L: The second term in the first bracket multiplies the second term in second bracket so both of the last terms are multiplying together EXAMPLEexpand: (X - 5) (X +2) = 0 1) X x X = X2 2) X x 2 = 2X 3) -5 x X = -5X 4) -5 x 2 = -10put it all together: X2 + 2X - 5X -10 =0 simplify: X2 -3X -10 = 0

HT

Related Maths GCSE answers

All answers ▸

Solve x^2+4x-5=0


How do we factorise an expression?


Johnny take 4 hours 50 minutes to drive 213 miles to Manchester. He then takes the train to Liverpool. Liverpool is 37 miles from Manchester and the train travels at 90mph. Calculate Johnny's average speed for his total journey in mph.


Factorise 2x^2+5x - 3