#4**+5 **

I just gave you 3 points Mari, I don't give points as easily as CPhill does. I like people to really earn them.

I am really pleased that you explained how you got your answer. It was your explanation - not your answer that earned you your points with me.

You sort of did what CPhill did - I will try to explain.

$$\dfrac{(x+4)}{2}=7$$

**You sort of said** : What divided by 2=7 and the answer is 14/2 is 7 This means that x+4=14

**CPhill said** : I want to get the x+4 on its own so how do I get rid of the 2 Umm I muliply by 2 but if I multiply the left side by 2 then i have to multiply the right side by2 as well. This keeps the equation balanced!

$$\begin{array}{rlll}

\frac{x+4}{2}&=&7\\\\

\frac{x+4}{2}\times 2&=&7\times 2\\\\

x+4&=&14\qquad \qquad \mbox{On the left the 2s cancel out, that is what CPhill did it for!}\\

\end{array}$$

**Next you said : **What + 4=14 and the answer is obviously 10 SO x=10

**CPhill said:** x+4=14 I need the x by itself so how do I get rid of the +4 Umm I know, I'll take it away (+4-4=0)

But if I take it away from the left side then I have to take it away from the right side too. I have to keep the equation balanced!

x+4**-4**=14**-4**

x=10

See you sort of did the same thing only CPhill did it in a more formal way.

You need to learn how to do it the formal way or you will not be able to solve difficult equations later on.

ALWAYS REMEMBER - EQUATIONS ARE LIKE SCALES, THEY MUST STAY BALANCED AT ALL TIMES!

Melody
Jul 21, 2014

#2**+5 **

i dont really get how to do it. i just subsitute the numbers to see which one makes sense and i got 10

(10+4)/2=7

add 10+4 then divide it by 2 and it =7

14/2=7

mari379
Jul 21, 2014

#3**+5 **

mari379, your "technique" will work* if *we're given the answers, beforehand.....!!!!

But, what if we** don't*** have* those???

Let's see how to solve this....step by step...

(x+4)/2=7 multiply both sides by 2

x + 4 = 14 subtract 4 from both sides

x = 10

In upper level maths....you * have* to be able to solve "without the answers"........also, "plugging" in the answers takes too much time in a test situation !!!!

CPhill
Jul 21, 2014

#4**+5 **

Best Answer

I just gave you 3 points Mari, I don't give points as easily as CPhill does. I like people to really earn them.

I am really pleased that you explained how you got your answer. It was your explanation - not your answer that earned you your points with me.

You sort of did what CPhill did - I will try to explain.

$$\dfrac{(x+4)}{2}=7$$

**You sort of said** : What divided by 2=7 and the answer is 14/2 is 7 This means that x+4=14

**CPhill said** : I want to get the x+4 on its own so how do I get rid of the 2 Umm I muliply by 2 but if I multiply the left side by 2 then i have to multiply the right side by2 as well. This keeps the equation balanced!

$$\begin{array}{rlll}

\frac{x+4}{2}&=&7\\\\

\frac{x+4}{2}\times 2&=&7\times 2\\\\

x+4&=&14\qquad \qquad \mbox{On the left the 2s cancel out, that is what CPhill did it for!}\\

\end{array}$$

**Next you said : **What + 4=14 and the answer is obviously 10 SO x=10

**CPhill said:** x+4=14 I need the x by itself so how do I get rid of the +4 Umm I know, I'll take it away (+4-4=0)

But if I take it away from the left side then I have to take it away from the right side too. I have to keep the equation balanced!

x+4**-4**=14**-4**

x=10

See you sort of did the same thing only CPhill did it in a more formal way.

You need to learn how to do it the formal way or you will not be able to solve difficult equations later on.

ALWAYS REMEMBER - EQUATIONS ARE LIKE SCALES, THEY MUST STAY BALANCED AT ALL TIMES!

Melody
Jul 21, 2014

#7**0 **

YES

When I was Queen Guinevere I would behead my unruly subjects!

And, now that I am a dinosaur I eat them for breakfast!

So you better tread VERY carefully. lol.

Melody
Jul 21, 2014

#8**0 **

Don't believe her for a minute, mari379.......her "bark" is worse than her "bite".....she's a "softy"....at heart.......

CPhill
Jul 21, 2014

#9**0 **

Yes CPhill your right!these kinda people are really very soft of heart!

I wonder , Zegroes is Godzilla and Godzilla is much more than dinosaur so it means that Godzilla is much more soft of heart than dinosaur!

A new secret of POOR Zeg-ROSE has been revealed!

rosala
Jul 21, 2014

#10**0 **

Sorry Chris

I didn't realise that it was a multiple choice answer. But it doesn't matter, my logic still holds.

And what do you mean

"My bark is worse than my bite" ?

Got you bluffed. Lol.

Anyway Mari it had been good to see you on the forum with the rest of CPhill's "Rat Pack".

Melody
Jul 21, 2014