-84
21x4=84 plus the negative
3x^2y^3+5x^3y^3-6+x^3y^2-2
= (3x^2y^3+5x^3y^3+x^3y^2)-(6+2)
= x^2y^2(3y+5xy+x)-8.
The final answer is x^2y^2(3y+5xy+x)-8~
Answer:

Step-by-step explanation:
<u>Step 1: Distribute
</u>



Answer:

<u>If needed solve for b
</u>



Simple...
you have

and

Just subtract...but first find a common denominator...
Use 40 as the common denominator...

and

So, subtract,

=

Thus, your answer.
D = r t
384 = 640 * t
384/640 = t
.6 = t .6 of an hour
.6 hr * 60min/1 hr = 36 minutes (just in case it needs to be in minutes)