Expand and simplify 4(x+5) + 3(x-7)

When we're doing algebra and expanding brackets, our first step is to multiply everything inside each bracket by what we have just before the bracket. Let's start with the 4(x+5). 4 lots of our unknown mystery number x would give us 4x. 4 lots of 5 gives us 20. So together we have 4x + 20. Doing the same for 3(x-7), 3 lots of x gives us 3x. 3 lots of -7 gives us -21. So all together we have 3x-21. Putting both parts together we have 4x + 20 + 3x - 21. Now we need to simplify this. If we write this in a different order with our x's together and our integers (or whole numbers) together we have 4x + 3x + 20 - 21. From here we can see we have 7x - 1. And there's our final answer.

CM
Answered by Connor M. Maths tutor

10223 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


How to calculate conditional probabilities? E.g, say we roll a fair standard six sided die, what is the probability we rolled a 2, given that the roll is even?


Solve the simultaneous equation: 3x+2y=8, 2x+5y=-2?


A is the point with coordinates (5, 9) B is the point with coordinates (d, 15) The gradient of the line AB is 3 Work out the value of d.


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