Question

[long]

-12 (x - 5) + 15 (6-x)=42

tìm x

Answer 1

[Nguyễn Lê Phước Thịnh]

\(-12\left(x-5\right)+15\left(6-x\right)=42\)

=>\(-12x+60+90-15x=42\)

=>-27x=42-150=-108

=>\(x=\dfrac{-108}{-27}=4\)

Answer 2

[Trịnh Minh Hoàng]

\(-12\left(x-5\right)+15\left(6-x\right)=42\\ \Rightarrow-12x+12\cdot5+15\cdot6-15\cdot x=42\\ \Rightarrow-12x+60+90-15x=42\\ \Rightarrow-27x+150=42\\ \Rightarrow-27x=42-150\\ \Rightarrow-27x=-108\\\Rightarrow x=-108:\left(-27\right)\\ \Rightarrow x=4\)