Write the following expression. The quantity 81 minus 5k, squared

81-25k²

Step-by-step explanation:

We need to write the expression for "The quantity 81 minus 5k, squared".

Square of any number x is given by x².

Square of 5k is given by : (5k)²= 5²×k²=25k²

Now subtract 25k² from 81.

It means we get : 81-25k². It is required expression.

425

Step-by-step explanation:

Y = 3 x 100 / 20. Y = 425%. 85 is 20 percent of 425.