How to expand brackets?

Expand 5(x - 4)

To expand the brackets, you must mutilpy the number outside the bracket by everything inside.

Step 1)  5 x x  =  5x

Step 2)  5 x (-4)  =  -20     Remember to include the minus sign

Adding the answers together, we get 5x - 20

 

The same method applies if there is a letter outside the brackets instead of a number.

Expand y(x + 3) 

Step 1)  x  =  xy

Step 2)  y x 3  =  3y

 

So y(x + 3)  =  xy +3y

 

Expand (x + 2)(+ 5)

 

To expand two sets of brackets, you need to multiply every term in the first bracket by every term in the second bracket. For example, multiply everything in the second bracket by x and then by 2:

Step 1)   y  =  xy

Step 2)   x x 5  =  5x

Step 3)   2 x y  =  2y

Step 4)   2 x 5  =  10

Now add the answers to the 4 steps together:

xy + 5x + 2+ 10

 

Expand (- 4)(- 1)

 

Step 1)  b  =  ab

Step 2)  x (-1) =  -a    Again, remember to incude the minus sign

Step 3)  (-4) x b  =  -4b

Step 4)  (-4) x (-1)  =  4

Together: aba - 4b+ 4

 

Exercises:

Expand all these brackets

 

3(+ 9)

2(8 + d)

z(2 - k)

-f(3 + h)

 

(c + 6)(d+ 2)

(s - 7)(t+ 9)

( uv)(g)

 

AC
Answered by Andy C. Maths tutor

13463 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Prove that the square of an odd number is always 1 more than a multiple of 4


Solve to find x: 32x + 43 = -8x - 17


Hairdresser A charges £66 for a haircut and has an offer of 1/3rd off. Hairdresser B charges £70 for a haircut and has an offer of 20% off. Which hairdresser is cheaper?


divide 352 into a ratio of 5:11


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences