Step-by-step explanation:
tanA=8/15 and tan B=40/9
tan(A+B)=(tanA+tanB)/1-tanAtanB
(8/15+40/9)/1-(8/15×40/9)
=-672/185
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.
Answer:
Step-by-step explanation:
3:12 can be simplified to 1:4
Answer:
No.
Step-by-step explanation:
A regular polygon has all sides and angles congruent. This is not possible with a concave polygon. If the sides are congruent in a concave polygon the angles are not congruent.
Answer:
D. $3.00
Step-by-step explanation:
3,500 multiplied by 3 is equal to $10,000