MYTUTOR SUBJECT ANSWERS

333 views

What are the set of values for x that satisfy the below equation?

x2 - 9x ≤ 36

1. Draw a graph.

y = x2 - 9x and y = 36

2. Find the points of intersection by solving x2 - 9x = 36

x2 - 9x = 36

x2 - 9x - 36 = 0

(x - 12)(x + 4) = 0

Therefore, the lines intersect at x = 12 and x = - 4

3. Either observe from your graph or plug in points either side of the points of intersection.

i) For x < -4

e.g. x = - 5. Sub. into LHS = (-5)2 - 9(-5) = 70 > 36

ii) For -4 < x < 12

e.g. x = 0. Sub. into LHS = 02 - 9(0) = 0 < 36

iii) For x > 12

e.g. x = 20. Sub. into LHS = 202 - 9(20) = 400 - 180 = 220 > 36

Therefore, x2 - 9x ≤ 36 when -4 ≤ x ≤ 12

Daisy D. A Level Chemistry tutor, GCSE Chemistry tutor, A Level Maths...

7 months ago

Answered by Daisy, an A Level Maths tutor with MyTutor


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

264 SUBJECT SPECIALISTS

£22 /hr

Ayyub A.

Degree: Mathematics Msci (Bachelors) - Bristol University

Subjects offered:Maths, Further Mathematics + 1 more

Maths
Further Mathematics
.MAT.

“Hi I'm Ayyub, current student at Bristol university studying Maths. I have significant tutoring experience in maths and hopefully i'll be able to help you out.”

£36 /hr

Joe B.

Degree: Mathematics G100 (Bachelors) - Bath University

Subjects offered:Maths, Further Mathematics + 4 more

Maths
Further Mathematics
Economics
.STEP.
.MAT.
-Personal Statements-

“About Me Hi, I'm Joe, a first year mathematics student from Luton studying at Bath University. I am an accomplished mathematician and economist, having achieved A* grades in A Level Maths, Further Maths and Economics in June 2016. As ...”

£24 /hr

Eilidh F.

Degree: Natural Sciences (Bachelors) - York University

Subjects offered:Maths, Further Mathematics + 2 more

Maths
Further Mathematics
Chemistry
Biology

“About me: My name is Eilidh (pronounced Aylee) and I am a student at the University of York. I study Natural Sciences specialising in Neuroscience, and have always loved both Science and Maths. I also reallyenjoy teaching, meeting new...”

About the author

£20 /hr

Daisy D.

Degree: Natural Sciences: Chemistry and Mathematics, MSci (Other) - Durham University

Subjects offered:Maths, Physics+ 2 more

Maths
Physics
Further Mathematics
Chemistry

“Hi, I'm Daisy! I'm currently in my 3rd year studying an integrated masters course in Natural Sciences (Chemistry and Maths) at Durham University. My main area of interest is the physcial side of both subjects. From a young age, I hav...”

MyTutor guarantee

You may also like...

Posts by Daisy

A stationary radium atom decays, emiting an alpha particle. Why is the recoil speed of the nucleus small compared to the alpha particle?

How do buffers work?

How do I find the molecule from the 1H NMR spectrum?

How is crude oil separated into fractions?

Other A Level Maths questions

How do i differentiate the equation y = x^2 + 6x + 2 with respect to x.

How do you do integration by parts?

The point P lies on the curve C: y=f(x) where f(x)=x^3-2x^2+6x-12 and has x coordinate 1. Find the equation of the line normal to C which passes through P.

How do you integrate 3x^2 - 6x + 5 (wrt x)?

View A Level 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