+0  
 
0
280
4
avatar

4=-3x+31 can u help urgent just started the unit so plz explain

Guest Jun 21, 2015

Best Answer 

 #1
avatar+91001 
+8

4=-3x+31

 

The aim is to get x by itself on the left hand side.

Before you can get x by itself you have to get the lots of x by itself.

So you want to get -3x by itself on one side.

ok, to do this you will need to get rid of +31

How can you do this?  Well you could take it away, but if you do then you will need to take it away from the other side as well because equations must stay balanced.

4=-3x+31

4-31=-3x+31-31

-27=-3x

-27=-3 * x

Now you need to get rid of the -3

What is the opposite of multiply by 3,  divide by 3 is and divide is the same as a fraction line.

$$\\-27=-3 * x\\\\
\frac{-27}{-3}=\frac{-3*x}{-3}\\\\
9=x \qquad $The -3's cancel out$\\\\
x=9$$

Melody  Jun 21, 2015
Sort: 

4+0 Answers

 #1
avatar+91001 
+8
Best Answer

4=-3x+31

 

The aim is to get x by itself on the left hand side.

Before you can get x by itself you have to get the lots of x by itself.

So you want to get -3x by itself on one side.

ok, to do this you will need to get rid of +31

How can you do this?  Well you could take it away, but if you do then you will need to take it away from the other side as well because equations must stay balanced.

4=-3x+31

4-31=-3x+31-31

-27=-3x

-27=-3 * x

Now you need to get rid of the -3

What is the opposite of multiply by 3,  divide by 3 is and divide is the same as a fraction line.

$$\\-27=-3 * x\\\\
\frac{-27}{-3}=\frac{-3*x}{-3}\\\\
9=x \qquad $The -3's cancel out$\\\\
x=9$$

Melody  Jun 21, 2015
 #2
avatar+4663 
+5

Nice Melody!!!

 

Well explained!!!

:D

MathsGod1  Jun 21, 2015
 #3
avatar+91001 
0

Thanks MG

Did you learn something from that ?

Melody  Jun 21, 2015
 #4
avatar+4663 
+5

I wanted a recap of what i learnt, i kinda did learn something.

 

Since you been teaching me that way i've been presenting my work like that.

 

Before i didn't add the divide bit with the fraction when dividing x to be just x. Usually i do it in my head.

MathsGod1  Jun 23, 2015

19 Online Users

avatar
avatar
avatar
avatar
We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details