Answer
$\text{approximately }602.08 \text{ pounds}$
Work Step by Step
Substituting $
A=600
$ and $
R=850
$ in the given equation, $
R=\sqrt{A^2+B^2}
,$ results to
\begin{array}{l}\require{cancel}
850=\sqrt{600^2+B^2}
\\
850=\sqrt{360,000+B^2}
.\end{array}
Squaring both sides and using the properties of equality, the equation above is equivalent to
\begin{array}{l}\require{cancel}
(850)^2=(\sqrt{360,000+B^2})^2
\\
722500=360,000+B^2
\\
722500-360,000=B^2
\\
362500=B^2
.\end{array}
Taking the square root of both sides, the equation above is equivalent to
\begin{array}{l}\require{cancel}
B=\sqrt{362500}
\\
B\approx602.08
.\end{array}
Hence, the force exerted by tractor B, $B,$ is $
\text{approximately }602.08 \text{ pounds}
.$
