tìm số nguyên x biết rằng a , 7 – | 63 – x | = 1535 – 287 – 1435 + ( – 13 ) b , ( 19x + 88 ) : 7 = ( 13 – 8)^2 – 8^2

0 bình luận về “tìm số nguyên x biết rằng a , 7 – | 63 – x | = 1535 – 287 – 1435 + ( – 13 ) b , ( 19x + 88 ) : 7 = ( 13 – 8)^2 – 8^2”

1. `a)7 – | 63 – x | = 1535 – 287 – 1435 + ( – 13 )`

   `→7-|63-x|=(1535-1435)+(-287-13)`

   `→7-|63-x|=100-300`

   `→7-|63-x|=-200`

   `→|63-x|=7-(-200)`

   `→|63-x|=207`

   `→` \(\left[ \begin{array}{l}63-x=207\\63-x=-207\end{array} \right.\) 

   `→` \(\left[ \begin{array}{l}x=-144\\x=270\end{array} \right.\)

   Vậy `x∈{-144;270}`

   `b)( 19x + 88 ) : 7 = ( 13 – 8)^2 – 8^2`

   `→(19x+88):7=5^2-8^2`

   `→(19x+88):7=-39`

   `→19x+88=-39.7`

   `→19x+88=-273`

   `→19x=-273-88`

   `→19x=-361`

   `→x=-361:19`

   `→x=-19`

   Vậy `x=-19`

   Bình luận

2. Đáp án:

    `a, ` \(\left[ \begin{array}{l}x= – 144\\x=270\end{array} \right.\) 

   `b,` `x = -19`

   Giải thích các bước giải:

   `a ,`

   `7 – | 63 – x | = 1535 – 287 – 1435 + ( – 13 )`

   `⇔“7 –  |63-x| = -200`

   `⇔“ |63-x| = 7 – ( – 200 )`

   `⇔“|63 -x | = 207`

   `⇒` \(\left[ \begin{array}{l}63-x =207\\63-x =-207\end{array} \right.\) 

   `⇒` \(\left[ \begin{array}{l}x= – 144\\x=270\end{array} \right.\) 

    _ _  _ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _ _ __ _ _ _ _ _ _ _  __ _ _  _ __  __ _  _ _ _ _ _  _ __ 

   `b ,`

   `( 19x + 88 ) : 7 = ( 13 – 8)^2 – 8^2`

   `( 19x + 88 ) : 7 = -39`

   `19x + 88 = -39 . 7`

   `19x  +88 = -273`

   `19x = -273 – 88`

   `19x = -361`

   `x = -361 : 19`

   `x = – 19`

   Bình luận