I watched an instructor write this question 3(x-7)=6, he then solved the Parentheses to get 3x-21=6, but here is where I was lost, he then added 21 on each side to get 3x=27, then divided each side by 3 to get x=9. Now, I always thought you you did everything in this order: Parentheses, Exponents, multiply/divide, then add/ subtract...but when I do this to this question, I got x-21=2, then x=23...can someone explain why he added/subtracted, before multiplied/divided, when trying to find the value of 'x'?
Subscribe to:
Post Comments (Atom)
analysis - Injection, making bijection
I have injection $f \colon A \rightarrow B$ and I want to get bijection. Can I just resting codomain to $f(A)$? I know that every function i...
-
Find all integer solutions of $2n \equiv 12 \bmod 19$ So I have re-arranged to: $2x-19y=12$ and by the extended Euclidean Algorithm, I get $...
-
Find the limit of the following-$$\lim\limits_{n \to \infty}\frac{2^{-n^2}}{\sum\limits_{k=n+1}^{\infty} 2^{-k^2}}$$ My work: We can see t...
-
I understand that a continued fraction of the form: $g(n_1,n_2,n_3,n_4,n_5,\ldots)= n_1 + \cfrac{1}{n_2 + \cfrac{1}{n_3 + \cfrac{1}{n_4 + \c...
No comments:
Post a Comment