Solve the equation 2.8x4-5x = 5.8 Solving practical problems with equations Two engineering teams jointly build a 3.9 km long highway, which will be completed in 20 days. It is known that team a builds 0.1 km per day, and team B how many km per day? Xiaoqing and her mother went to the shopping mall to buy two boxes of chocolate, 59.8 yuan per box, and 4.5 kg of candy, 14.6 yuan per kg. How much did they spend?

2.8x4-5x=5.8
11.2-5.8=5x
5.4=5x
x=1.08
1. Set up team B to repair x kilometers per day
20×0.1+20X=3.9
20X=3.9-2
20X=1.9
X=0.095
2、2×59.8+4.5×14.6＝185.3

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