\(C=\dfrac{x^2-x-30}{x^2-25}=\dfrac{\left(x^2-6x\right)+\left(5x-30\right)}{\left(x+5\right)\left(x-5\right)}\)

\(=\dfrac{\left(x-6\right)\left(x+5\right)}{\left(x-5\right)\left(x+5\right)}=\dfrac{x-6}{x-5}\)

Circle the correct answer A, B, C, or D to complete each of the following sentences

The students are _____________ judo in the gym now.

A. making

B. going

C. being

D. doing

Circle the word that has the underlined part pronounced differently from the rest

A. archery

B. change

C. watch

D. schedule

Mark the letter A, B, C, or D to indicate the word or phrase OPPOSITE in meaning to the bold and underlined part in each of the following questions.

Names of the people in the book were changed to preserve anonymity.

A. reveal

B. cover

C. presume

D. conserve

\(x^2-16=0\)

\(\Leftrightarrow x^2-4^2=0\)

\(\Leftrightarrow\left(x+4\right)\left(x-4\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-4=0\\x+4=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=4\\x=-4\end{matrix}\right.\)

Vậy \(x=4;-4\)

Bạn xét a+b+c=0 và a+b+c khác 0