Let A, b, h be, respectively, the area, base and height of the parallelogram. Then, the area of a parallelogram is given by
[tex]A = \dfrac{1}{2}bh[/tex]
Plugging the known values for A and h, we have
[tex]\dfrac{35}{42}=\dfrac{1}{2}\cdot b \cdot \dfrac{1}{7}[/tex]
We can multiply both sides by 14 to get
[tex]\dfrac{35}{3}=b[/tex]