Answer:
The required expression is 3x²+ 3x.
Step-by-step explanation:
It is given that Ricardo and Kim rowed their canoes from their base camp to a fishing camp.
They rowed a distance of x miles upstream on one river, (3x²-9) miles downstream on another river, and (2x + 9) miles across a calm lake.
Distance covered in upstream = x miles
Distance covered in downstream = (3x²-9) miles
Distance covered in calm lake = (2x+9) miles
Total distance covered by Ricardo and Kim is
[tex]D=x+(3x^2-9)+(2x+9)[/tex]
On combining like terms we get
[tex]D=3x^2+(x+2x)+(-9+9)[/tex]
[tex]D=3x^2+3x+0[/tex]
[tex]D=3x^2+3x[/tex]
Therefore the required expression is 3x²+ 3x.
