f(x) = 5 – x and g(x) = 3x + 7 (a) Simplify f(2x) + g(x – 1)

May look hard at first but once understood is simple.Question is asking to add two functions together.Firstly we begin by calculation f(2x) We know that f(x) = 5 – x, to find f(2x) we replace the x by 2xThis gives us f(2x) = 2 -2xNext we calculate g(x-1) this one is a little trickier but follows the same ideawe know that g(x) = 3x +7, to find g(x-1) we replace the x by (x-1)This gives us g(x-1) = 3(x-1) +7 We then expand the brackets to find g(x-1) = 3x-3 +7Therefore f(2x) + g(x-1) = 2-2x +3x-3+7= 9 + x

MB
Answered by Matthew B. Maths tutor

4450 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

expand (x-3)^2


Here are four fractions, 4/5 3/8 12/30 14/20. Write them in order of size, starting with the smallest fraction.


Ms Henderson has two jars of sweets. The jars contain the same number of sweets in total. 25% of the sweets in Jar A are mint. Two fifths of the sweets in Jar B are mint. There are 10 mint sweets in Jar A, how many mint sweets are there in Jar B?


Talil is going to make some concrete mix. He needs to mix cement, sand and gravel (1: 3:5) by weight. Talil wants to make 180 kg of concrete mix. He has 15 kg of cement, 85 kg of sand, 100 kg of gravel. Does he have enough to make the concrete?


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