Answer:
Step-by-step explanation:
[tex]a = b \times h \\ \\ a = 9 \: \: {yd}^{2} \\ b = 6 \: \: yd \\ \\ 9 = 6 \times h \\ h = \frac{9}{6} \\ h = 1.5 \: \: yd[/tex]
I hope that is useful for you :)
