hi,
You have to use a formula which is known as of binomial coefficient which is :
k among n is : C ( n /k) = n! / k! ( n-k)!
! = factorial
ex : 5 object among 8 is : C ( 8/5 ) = 8 ! / 5! * ( 8-5) !
As 8! = 8*7*6*5*4*3*2*1 = 40 320
As 5! = 5*4*3*2*1 = 120
as 3 ! = 3*2*1 = 6
then : 40 320 / 120 * 6
40 320 / 720 = 56
Conclusion : there is 56 way to select 5 object among 8 of them.
ps : you can also use Pascal Triangle to do such a thing.
You have:
2r

6r-21
then move the 6r over to the left and you end up wtih
-4r

-21
Then you divide by -4 and when you do you must flip the inequality so your answer would be
r

21/4
Step-by-step explanation:
Angle:2x+30+3x=180
Angle:2x+b+2b=180( Being in straight line)
Angle:30+3x+a=180
The area of the shaded region will be the area of the rectangle minus the area of the white square inside of it:
((x+10)(2x+5)) - ((x+1)(x+1))
First, FOIL both of the areas separately:
(2x^2 + 5x + 20x + 50) - (x^2 + x + x + 1)
Simplify within the parentheses by adding like terms:
(2x^2 + 25x + 50) - (x^2 + 2x + 1)
Now, subtract one equation from the other:
2x^2 + 25x + 50
-x^2 - 2x - 1
= x^2 + 23x + 49
This will be the equation for the area.
Hi there!
When the slopes of two perpendicular lines are multiplied the outcome will be -1.
The slope is the number that is positioned in front of the variable x in the formula. In this case the slope of the given line is -2/5.
Let's call the slope of the perpendicular line m and take into account the given data of the question and my earlier explanation. We then find the following:

Divide both sides by - 2/5.

The answer is B.
~ Hope this helps you!