MYTUTOR SUBJECT ANSWERS

2458 views

Solve: 3(x - 2) = 21

First you look at BIDMAS, which determines the order in which functions are completed, [Brackets, Indices, Division, Multiplication, Addition, Subtraction], which says we deal with the brackets first, so we expand the bracket by multiplying everything in the bracket by whats outside it; in this case 3.

3x - 6 = 21

We then need to reaarange the equation to get x on its own, remember that when anything goes over to the other side of an equals sign it changes to the opposite of its function (positive - negative or multiply - divide). So the -6 goes across and becomes a positive 6:

3x = 21 + 6

3x = 27

Then the multiply by three goes over and becomes a divide:

x = 27/3

x = 9

Mia V. GCSE Chemistry tutor, A Level Chemistry tutor, GCSE Maths tuto...

1 year ago

Answered by Mia, a GCSE Maths tutor with MyTutor


Still stuck? Get one-to-one help from a personally interviewed subject specialist

570 SUBJECT SPECIALISTS

£22 /hr

Sanskrithi S.

Degree: Medicine (Other) - Oxford, University College University

Subjects offered:Maths, Chemistry+ 6 more

Maths
Chemistry
Biology
.UKCAT.
.BMAT (BioMedical Admissions)
-Personal Statements-
-Oxbridge Preparation-
-Medical School Preparation-

“I am a third year medical student at the University of Oxford whose aim is to support and guide students in their science studies.”

MyTutor guarantee

|  4 completed tutorials

£18 /hr

Emma B.

Degree: Mechanical Engineering (Masters) - Southampton University

Subjects offered:Maths, Physics+ 1 more

Maths
Physics
Design & Technology

“A positive and bubbly tutor who will put 100% into helping your child succeed and discover their passion for learning!”

£18 /hr

Qasim J.

Degree: Medicine (Bachelors) - Birmingham University

Subjects offered:Maths, Chemistry+ 3 more

Maths
Chemistry
Biology
-Personal Statements-
-Medical School Preparation-

“A 4th year medical student with an adaptable and organised approach. Well-planned revision with exam practice ensures knowledge and fantastic exam technique!”

Trusted by schools

|  2 completed tutorials

About the author

Mia V.

Currently unavailable:

Degree: Chemistry (Masters) - Durham University

Subjects offered:Maths, Physics+ 1 more

Maths
Physics
Chemistry

“I am a Chemistry student at Durham University. I've always had a passion for learning new things, but most importantly helping others to learn new things too! I'm an open, patient individual who aims to put you at ease with your scien...”

You may also like...

Posts by Mia

A pendulum has a frequency of 0.80 Hz, calculate the periodic time of the pendulum.

Explain why fluorine and chlorine are in the same group of the periodic table.

Solve: 3(x - 2) = 21

What is a disproportionation reaction?

Other GCSE Maths questions

How do you work out the length of one of the sides of a right-angled triangle given the other two?

Frank, Mary and Seth shared some sweets in the ratio 4:5:7. Seth got 18 more sweets than Frank. Work out the total number of sweets they shared.

blah blah blah

Write the recurring decimal 0.0755... as a fraction in its lowest terms

View GCSE Maths tutors

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok