Answer:
(x - 9)(x + 9)
Step-by-step explanation:
x² - 81 ← is a difference of squares and factors in general as
a² - b² = (a - b)(a + b), then
x² - 81
= x² - 9²
= (x - 9)(x + 9)
Answer:
80 percent of 70 is 56, so you were 20% wrong?
The percent error is 20%
let me know if you need anything else :)
Answer:
x= number of songs bought
y= number of movies bought
1.75*x + 2.5*y = 45
x + y = 20
Step-by-step explanation:
Giving the following information:
Robert spent $45 buying songs and movies at an online store that charges 1.75 for each song and $2.50 for each movie he purchased a total of 20 songs and movies combined.
<u>We need to establish a system of equations that represents this situation.</u>
x= number of songs bought
y= number of movies bought
1.75*x + 2.5*y = 45
x + y = 20
<u>Now, we can determine the x and y:</u>
x= 20 - y
Substitute x:
1.75*(20 - y) + 2.5y = 45
35 - 1.75y + 2.5y = 45
0.75y = 10
y= 13
x= 20 - 13
x= 7
<u>Prove:</u>
1.75*7 + 2.5*13 = 45
7 + 13 = 20
27+19 can be re-written as : 19+27
Now we can add them.
19
+27
-------
46
Our final answer: 46
Know: 17.35 is equivalent to 4 burgers 3 med fries
6.09 Is equivalent to 1 burger med fries
9.34 8s equivalent to 2 burgers med fries and med drink
So what you want to do is take 6.09 and subtract it from 9.34 which is 3.25. Now 3.25 is your burger price.
What you want to do now is take your 3.25 and multiply it by 4 which would be 13. 17.35 subtract 13 would be 4.
4 divided by 3 is 1.33 which is now the price of a med fries.
now for the drink. 3.25 plus 1.33 is 4.58.
6.09 subtract 4.58 is 1.51
Now you have 3.25 as your burger
1.33 as your fries
1.52 for your drink