Ta có: \(\left\{{}\begin{matrix}x_1=64t\left(km;h\right)\\x_2=180-40t\left(km;h\right)\end{matrix}\right.\)
Khi 2 xe gặp nhau: \(x_1=x_2\)
\(\Leftrightarrow64t=180-40t\)
\(\Leftrightarrow t=\dfrac{45}{26}h=1h44p\)
Cách B: \(180-40\cdot\dfrac{45}{26}\approx110,7\left(km\right)\)