Show that (4+√12)(5-√3)= 14+6√3

First, expand out the brackets. Initially, this will give you 20 - 4√3 + 5√12 - √36.

√36 is the equivalent of 6, now giving up 20 - 4√3 + 5√12 - 6. We can combine the 20 and the 6 to give us 14 - 4√3 + 5√12.

Now, let's look at 5√12. √12 is the same as √4 x √3. √4 is the same as 2, so we have 2√3. We then substitute in 2√3 as √12, giving us 5(2√3). This then becomes 10√3.

We then have 14 - 4√3 + 10√3. We can then do 10√3 - 4√3, which gives us 6√3.

Altogether, this gives us our answer of 14 + 6√3!

LH
Answered by Lucy H. Maths tutor

9679 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Why do square roots have more than 1 solution?


A scalene triangle PQR, where PQ is (3x+4)m long, QR is (2-x)m long and angle PQR is 30 degrees, has an area of 2 square metres. Find x.


f(x) = (x+1)^2 and g(x) = 2(x-1); Show that gf(x) =2x(x+2)


How do I solve simultaneous equations that aren't linear, for example x^2 + 2y = 9, y = x + 3


We're here to help

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

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning