Prime numbers are numbers that have only one factor pair; 1 and themselves.
Let's start from 21.
21 = 1 x 21, 3 x 7.
This has two factor pairs, this is not prime.
Let's try 22.
22 = 1 x 22, 2 x 11.
This also has two factor pairs, this is not prime.
Let's try 23.
1 x 23.
This is a prime number, as it only has one factor pair; 1 and itself.
23 is your prime number.
I hope this helps!
This looks like a parabola so:
y=x^2 - 20x + 15 --> x^2 - 20x +15=y
(x^2 -20x)=y - 15 --> (x - 10)^2=y - 15 +100 ( used complete the square)
(x - 10)^2=y + 85
1x•4x•5x=180
10x=180
10/10x=180/10
X= 18
$5.49 per hamburger x 2 hamburgers=$10.98
$1.75 per soda x 4 sodas=$7
$10.98+$6.25+$12.99+$7=$37.22
$37.22 x 0.07 sales tax=approximately $2.61
$37.22 x 0.2 tip=approximately $7.44
$37.22+$2.61+$7.44=$47.27
2/3,2/6,2/8
23 is the greatest because it has larger pieces
2/6 is the second greatest because it is a little smaller than thirds
2/8 is the least because it has the smallest pieces
