So you need to find the width of the rectangle, as area is length times width, and we have width already.

Perimeter=2*length + 2*width = 200 (2 meters=200 centimeters).

plug in that length = 70.

2*70 + 2*w=200.

Subtract 140 from both sides

2*w=60

Divide by 2

w=30.

Area equals length times width

A=w*l

A=30*70

So the area is 210