Question

metoda mersului invers:[495-(x÷3)]×5=975,,,,,,,,42÷(x×x-58)+800÷(10×28-10×18=15

Answer 1

[ 495 - ( x : 3 ) ] × 5 = 975

495 - ( x : 3 ) = 975 : 5

495 - x : 3 = 195

x : 3 = 495 - 195

x : 3 = 300

x = 300 × 3

x = 900 → numarul, aflat prin metoda mersului invers

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42 : ( x · x - 58 ) + 800 : ( 10 × 28 - 10 × 18 ) = 15

42 : ( x · x - 58 ) + 800 : ( 280 - 180 ) = 15

42 : ( x · x - 58 )  + 800 : 100 = 15

42 : ( x · x - 58 )  + 8 = 15

42 : ( x · x - 58 )  = 15 - 8

x · x - 58 = 42 : 7

x · x - 58 = 6

x · x = 6 + 58

x · x = 64

x = 8 → numarul, aflat prin metoda mersului invers