Question 459666
1. Estimate the value of the square root:0.85
<pre>
To estimate the square root of 0.85, we know that the
square root of 81 is 9 and therefore the square root
of 0.81 is 0.9.  So we begin with 0.9 

Now we subtract the last digit of 0.81, which is 1,
from the last digit of 0.85, which is 5, and get 4,
then we take half of 4 and get 2.

Then we put 2 on the end of 0.9 and get 0.92. That's
the estimation.

By the calculator we get 0.9219544457 so 0.92 is
a very good approximation.

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</pre>
2.Write -4 x y x y x y using exponents
<pre>
Count the x's to be multiplied.  There are 3 of them,
so that's x³

Count the y's to be multiplied.  There are 3 of them
also, so that's y³.  So we write

-4x³y³

Edwin</pre>