Question

Tìm x thỏa mãn :-12(x-5)+7(3-x)=5

Answer 1

\(\Rightarrow\left(-12x-\left(-60\right)\right)+\left(21-7x\right)=5\)

\(\Rightarrow-12+60+21-7x=5\)

\(\Rightarrow-12x-7x+60+21=5\)

\(\Rightarrow-19x+81=5\)

\(\Rightarrow-19x=5-81\)

\(\Rightarrow-19x=-76\)

\(\Rightarrow x=-76\div\left(-19\right)\)

\(\Rightarrow x=4\)

KL x=4