(x+2x)*2=30
x=5
5cm in width and 10cm in length.
The area is 10*5=50 square centimeters.
Set a small passenger plane to fly x meters per hour.
4x-320= 1080
4x= 1400
x=350
A: The speed of the passenger plane is 350 kilometers per hour, which is 350,000 meters.
Suppose xiaoxiao is x years old.
x+27=4x
3x=27
x=9
4*9=36
A Xiaoxiao is 9 years old and her mother is 36 years old.
Suppose b travels x kilometers per hour.
20x-36*20=50
20x=770
x=38.5
Answer B: The speed is 38.5 kilometers per hour.
Coordinates of point C: x=(0+6)/2=3, y=(0+0)/2=0. So c (3 3,0).
The coordinate of the symmetrical point C' of point C about the Y axis is (-3,0).<