Master Algebra Revision with Exam Tips & Methods | Boost Your Summer Exam Prep

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FocusMaths
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Homework Statement
4x+5=3x+6
Relevant Equations
Find X
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have a Summer Exam , at the begging of next week on all topics that we have done , so I decided to do Algebra , but I forgot have to do it , because it was a while ago, can anyone show me the method again please to memorize.
Thanks in advance .
Workings : add 4x+5=9
3x+6=9
9/3 =3/3
3x=3
 
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Welcome to the PF. :smile:

Do the same thing to both sides of the equation at the same time to simplify it. Try subtracting 5 from both sides of the equation. Then subtract 3x from both sides. What do you get when you do this? Can you show your work using those hints?
 
4x-3x+5-5=6-5=
1X/1=1/1
X=1
 
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Is it correct and thanks
 
FocusMaths said:
Is it correct and thanks
Yes. And if the problem were a little different, you might have to multiply or divide both sides of the equation to simplify it.

If you ended up with 3x = 7, how would you solve for x?
 
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FocusMaths said:
Problem Statement: 4x+5=3x+6
Relevant Equations: Find X

Workings : add 4x+5=9
3x+6=9
9/3 =3/3
3x=3
Your work only makes sense if you happen to know the solution in advance.
Start with the original equation: 4x + 5 = 3x + 6
a) Get all the terms involving x on one side, and b) get all the constants on the other side.
For the a) part, add -3x to both sides of the equation:
4x + (-3x) + 5 = 3x + (-3x) + 6
Simplify to x + 5 = 6
For the b) part, add -5 to both sides:
x + 5 + (-5) = 6 + (-5)
Simplify:
x = 1

Check by substituting 1 for x in the original equation:
4(1) + 5 = 3(1) + 6, or 9 = 9, a true statement.
 
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