Answer:
0,4
Step-by-step explanation:
90 feet
30x3=90
5x - 9 = -30
"Nine less than" means - 9
"Five times a number" means 5*unknown number = 5x
5184
9 squared is 81 (9 x 9)
8 squared is 64 (8 x 8)
64 x 81 is 5184