Solution: 200 x+1100-50x =1400.
150 x+ 1 100- 100 = 1400- 1 100
150 x÷ 150 = 300÷ 150
x=2
② 10x-5( 10-x)=55
Solution: 10x-50+5x = 55
15x-50+50=55+50
15x÷ 15 = 105÷ 15
x=7
③ 3(x+5)+2x=5×6
Solution: 3x+ 15+2x = 30.
5x+ 15- 15 = 30- 15
5x \5 = 15 \5
x=3
What courses are there in the Department of Ophthalmology and Optics of Xiamen University?
Public basic courses: advanced mathematics (1), English,