Add the three angles and set them to 180
4x-13+15+x+18=180
5x+20=180
5x=160
x=32
Then plug in to get A and C
A=4*32-13
A=115
C=32+18
C=50
Answer:
3 minutes
Step-by-step explanation:
To find how many minutes it will take to play the whole song, multiply 1/5 by 15
15(1/5)
= 3
So, it will take 3 minutes to play the whole song
$2.10 - $2 = $0.10
The banana cost 10 cents.
Answer: It is a difference of two squares, and it factors to (3x-7)(3x+7)
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Explanation:
We can write the 9x^2 as (3x)^2 since
(3x)^2 = (3x)*(3x) = (3*3)*(x*x) = 9x^2
The 49 can be written as 7^2 because 7^2 = 7*7 = 49.
This means 9x^2 - 49 is the same as (3x)^2 - 7^2. We have a difference of two squares.
The difference of squares factoring rule is
a^2 - b^2 = (a-b)(a+b)
which we have a = 3x and b = 7 in this case
So,
a^2 - b^2 = (a-b)(a+b)
(3x)^2 - 7^2 = (3x-7)(3x+7)
9x^2 - 49 = (3x-7)(3x+7)
Side note: This is the same as (3x+7)(3x-7). We can multiply two numbers in any order.
