Any answers plzzzzzz

Answer:
A = 3[tex]r^{2}[/tex]
Step-by-step explanation:
r = [tex]\sqrt{\frac{A}{3} }[/tex]
r = [tex](\frac{A}{3})^{1/2}[/tex]
square both sides:
[tex]r^{2}[/tex] = [tex]\frac{A}{3}[/tex]
multiply 3 to both sides:
3[tex]r^{2}[/tex] = A
Answer:
[tex] a= 3r {}^{2} [/tex]
[tex] \sqrt{ \frac{a}{3} } = r \\ \frac{1}{3a} = r {}^{2} \\ \frac{1}{3a} \frac{1}{3} = r {}^{2} \frac{1}{3} \\ a = 3r {}^{2} [/tex]