Please help me, this is geometry and I will give brainliest

Answer:
15 and 45 mm
Step-by-step explanation:
formula for the area of a rhombus: [tex]A=\frac{d_{1} d_{2} }{2}[/tex]
[tex]337.5=\frac{3d*d}{2}[/tex]
[tex]337.5=\frac{3d^2}{2}[/tex]
[tex]675=3d^2[/tex]
[tex]225=d^2[/tex]
[tex]d= 15, d=-15[/tex]
one diagonal equals 15, the other one 15*3=45