MYTUTOR SUBJECT ANSWERS

353 views

a) You area told that y is proportional to x2 and that when y = 75, x = 5. Find a formula for y in terms of x. y = x b) Find the value of y when x = 3. c) Find the value of x when y = 1200.

a) y is proportional to x^2, when x is 5, y is 75

Therefore: 75 = (something multiplied by) 5^2

75 = 3 x 25

Hence y = 3x^2

b) y = 3 multiplied by 3^2 

= 27

c) 1200 = 3x^2

1200/3 = x^2

400 = x^2

Undo the square of x (on both sides!)

x = 20

Kezia  M. GCSE Maths tutor, 13 plus  Maths tutor, 11 Plus Maths tutor...

11 months ago

Answered by Kezia , a GCSE Maths tutor with MyTutor


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

458 SUBJECT SPECIALISTS

£18 /hr

Solomon L.

Degree: Mathematics (Bachelors) - Leeds University

Subjects offered: Maths, Further Mathematics

Maths
Further Mathematics

“Currently studying at Leeds university, ready to help you improve your grades in Maths and Chemistry GCSE! ”

£18 /hr

Laura P.

Degree: Natural Sciences (Masters) - Lancaster University

Subjects offered: Maths

Maths

“Hi! I'm Laura, a Natural Scientist at Lancadter University, where I study Maths and Phyiscs. I have such a passion for these subjects that I hope my tutorials will be both engaging and interactive, because the best way of learning is ...”

£18 /hr

Leo P.

Degree: Theoretical Physics (Masters) - University College London University

Subjects offered: Maths, Further Mathematics

Maths
Further Mathematics

“About Me: I am a MSci Theoritical Physics student at University College London (UCL). Maths is everywhere and that's what I love about maths. Hopefully you'll enjoy it too I am a friendly, understanding and patient tutor that enjoys t...”

MyTutor guarantee

About the author

Kezia M.

Currently unavailable: for regular students

Degree: Medicine (Bachelors) - Southampton University

Subjects offered: Maths, Chemistry+ 2 more

Maths
Chemistry
Biology
-Medical School Preparation-

“Who am I?I am a second year medical student at the University of Southampton. I absolutely love the course and am very excited to share my love for the subject with other students!I am very organised and patient as well as being ap...”

MyTutor guarantee

You may also like...

Other GCSE Maths questions

A circle with centre C has equation x^2 + y^2 + 2x - 6y - 40 = 0. Express as (x - a)^2 + (y - b)^2 = d.

Solve this pair of simultaneous equations: 3x + y= 7 and 3x - y = 5

expand the brackets (x+5)(x+3) furthermore what are the two values of x

Find the nth term of the sequence 7,11,15,19...

View GCSE Maths tutors

Cookies:

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

mtw:mercury1:status:ok