#### Answer

z=21

#### Work Step by Step

In order to solve for d the proportion $\frac{6}{10}$=$\frac{z}{35}$, we must apply the Cross Products Property of a Proportion that states that if $\frac{a}{b}$=$\frac{c}{d}$, where b$\ne$0 and d$\ne$0, then ad=bc.
We'll set a=6, b=10, c=z and d=35, and apply the Property.
$\frac{6}{10}$=$\frac{z}{35}$
(6)(35)=(z)(10)
210=10z
Then, to solve for a, we'll divide by 10 on both sides of the equation
$\frac{210}{10}$=$\frac{10z}{10}$
z=$\frac{210}{10}$=21