Answer:
= 21x - 1
Step-by-step explanation:
= (4x + 12x) + (5x - 1)
= 4x + 12x + 5x - 1
= 16x + 5x - 1
= 21x - 1
Answer:

Step-by-step explanation:
We can use exponent rules to try and simplify this expression down.
Exponent rules tell us that
.
This means that since we have the same base on both terms (7 and 7), we can add the exponents to get a simplified expression.

So our simplified expression is
.
Hope this helped!
So, she has 3hrs to grade all papers, for 35 students.. alrite.
the first 5, she does them in 30minutes.. what's the speed rate? well, 5/30 or 1/6
now, she has still 2 hours and a half, or 150 minutes, to do the remaining 30 papers... she has to work at a rate of 30/150 then... which is 1/5 simplified.
now if we take 1/6 as the 100%, what is 1/5 in percentage then?

so 1/5 is 120% in relation to 1/6... meaning the rate of 1/5 she needs to move through, namely 1 paper every 5 minutes, is 20% faster than 1/6.