Question

(7×3-x×4)×9+107=152 vreau si eu o rezolvare ca sa inteleaga si un copil de clasa a3a

Answer 1

(7×3-x×4)×9+107=152
(21-x×4)×9=152-107
(21-x×4)×9=45
21-x×4=45:9
21-x×4=5
x×4=21-5
x×4=16
x=16:4
x=4

Answer 2

In clasele primare se face prin metoda mersului invers:
$(7 \times 3 - x \times 4) \times 9 + 107 = 152 \\ (7 \times 3 - x \times 4) \times 9 = 152 - 107 \\ (7 \times 3 - x \times 4) \times 9 = 45 \\ 7 \times 3 - x \times 4 = 45 \div 9 \\ 7 \times 3 - x \times 4 = 5 \\ 21 - x \times 4 =5 \\ 21 - 4x = 5 \\ 21 - 5 = 4 \times x \\ 16 = 4 \times x \\ 16 \div 4 = x \times 4 \div 4 \\ 4 = x$
Deci x = 4. Sper sa intelegi :)