[tex]a)5x = - 10 \\ x = - 10 \div 5 \\ x = - 2 \\ \\ b) - 3x = 3 {}^{2} \\ x = 3 {}^{2} \div - 3 \\ x = - 3 {}^{2 - 1} \\ x = - 3 \\ \\ [/tex]
[tex]c) - 6x = - 2 \times 3 {}^{3} \\ - 6x = - 2 \times 27\\ - 6x = - 54 \\ x = - 54 \div (- 6 )\\ x = 9[/tex]
[tex] d) - 2 {}^{2} \times 7 {}^{3} = 7 {}^{2} \times x \\ x = - 2 {}^{2} \times 7 {}^{3} \div 7 {}^{2} \\ x = - 2 {}^{2} \times {7}^{3 - 2} \\ x = - 4 \times 7 \\ x = - 28[/tex]
[tex]e) - 2 {}^{2} \times 3 = - 6x \\ - 4 \times 3 = - 6x \\ - 6x = - 12 \\ x = - 12 \div ( -6) \\ x = 2[/tex]
[tex]f)(2 + 3)x = - 15 \\ 5x = - 15 \\ x = - 15 \div 5 \\ x = - 3[/tex]
[tex]g)(79 - 84)x = - 10 \\ - 5x = - 10 \\ x = - 10 \div ( - 5) \\ x = 2[/tex]
_______EXPLICAȚII_______
Regula semnelor:
LA ÎMPĂRȚIRE:
MINUS : MINUS = PLUS
PLUS : PLUS = PLUS
MINUS : PLUS = MINUS
PLUS : MINUS = MINUS
LA ÎNMULȚIRE:
MINUS • MINUS = PLUS
PLUS • PLUS = PLUS
MINUS • PLUS = MINUS
PLUS • MINUS = MINUS
