Basic Math/Math

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Question
If I have an equation, let's say x= 9, to find x u just plug in a value where the x is to make the statement true. Do you use this same concept when we are finding what  x really is, for instance a more complicated equation such as 25x+ 2=52 . when u solve the equation and get x=2, when u get this simpler equation do u plug in the 2 to the simplier one because that is what the value is? Also does the equal sign mean 'is', like does it mean a number x is 2. Thank you so much if you could answer this. I love math but this simple detail is messing me up and I just wish someone could clear this up because my teacher sure can' t lol.

Answer
Yes, that is one way of looking at it. Although I don't suggest using that method since you will get to a point where there are just too many numbers to guess. What you should do instead is to simplify the equation. So let's take your example again of 25x+2=52

Since it's an equation, we want to isolate the variable, meaning to make it so that the variable is equal to a number. So in this case, we want the 2 from the 25x+2 side gone. We can subtract 2 from both sides to arrive at 25x=50. Now, we can divide 25x by 25 to get one lone x, which is equal to 50/2=25.

So let's try another example. 27-8x=3

We can isolate the x by subtracting 27 from both sides, giving you -8x=-24
We can then divide (don't forget that you have to use PEMDAS in the opposite direction when simplifying) by -8, giving us x=3

And yes, "is" is the same thing as "=."

Sorry for the late response. I haven't been receiving updates from allexperts. I hope this answer finds you in time.

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Hsin Tung

Expertise

Anything from elementary to high school is fair game. I'm also experienced in standardized testing, such as SAT subject test math level 2, SAT math portion, and AP Calculus exam. The only problems I will have difficulty in are those that have no relevance to Algebra itself such as Geometry and number theory.

Experience

I have taken: Algebra, Geometry, Algebra 2, Math Analysis (Pre-Calculus), and AP Calculus AB. I have received all A's for each year other than one semester in Math Analysis when I was transferring schools. I tutor after school at the library, usually focusing on Algebra for the most part.

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I am: Officer of Asian club; President of SAFE club; KDE-RC1 Judge

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770 on SAT math portion, 5 on AP Calculus Exam, and 750 on SAT subject test math level 2

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John's Hopkins CTY award; OOCE Accounting (1st Place); FBLA Sections for Business Calculations (2nd)

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