Answer:
w² +9w +20
Step-by-step explanation:
Multiply it out, collect terms, and write as descending powers of w.
(5+w)(w+4) = 5w +5·4 +w² +w·4
= w² +9w +20
So it is really easy to solve firstly we can see how much does the first 10 boxes make which makes around 75$ obviously. Secondly 55$ for the next 10 boxes.
So for now we can simply calculate that we have spent around 130$ which means 20 boxes. The remaining money left is 18$ so we can buy 18/4.5 = 4 only 4 boxes with that money. Hence a total of 24 boxes.
The expression 36x² - 121 is in the 'difference of two squares form' which is (a² - b²)
Factorising (a² - b²) gives (a+b)(a-b)
Factorising 36x² - 121 gives (6x+11)(6x-11)
Answer is 12
Reason
Combine like terms
3x + 99 x = 1224
102x = 1224
Now solve for x
Divide both sides by 102
x= 12
B. 361/4
you get: x^2-19x+361/4=(x-19/2)^2