Question

Thực hiện phép tính: 5x(12x+7)-(3x+1)(20x-5)

Answer 1

60x+35-60x-5

(=)25

Answer 2

\(5x\left(12x+7\right)-\left(3x+1\right)\left(20x-5\right)\)

\(=60x^2+35x-\left(60x^2-15x+20x-5\right)\)

\(=60x^2+35x-60x^2+15x-20x+5\)

\(=20x+5\)

học tốt

Answer 3

\(5x\left(12x+7\right)-\left(3x+1\right)\left(20x-5\right)\)

\(=60x^2-35x-\left(60x^2-15x+20x-5\right)\)

\(=60x^2-35x-60x^2+15x-20x+5\)

\(=\left(60x^2-60x^2\right)-35x+15x-20x+5\)

\(=-20x+5\)