The rule to remember about generating the perpendicular family to a line is we swap the coefficients on and x and y, remembering to negate one of them. Then the constant is set directly from the intersecting point.
So we have
y = 3x + 2
-3x + 1y = 2
Swapping and negating gets the perpendiculars; the constant is as yet undetermined.
1x + 3y = constant
Since we want to go through (0,2), we could have just written
x + 3y = 0 + 3(2) = 6
3y = -x + 6
y = (-1/3) x + 2
Third choice
The result of rolling a number cube 7 times is a 7-digit number composed of digits 1,2,3,4,5 and 6 so that digits can repeat. The total number of possibilities is 6^7.
The number of possibilities where 4 appears exactly two times is 5^5*(7!-6!/2).
5^5 is the number of 5-digits numbers composed of digits 1,2,3,5 and 6 so that digits can repeat.
7! is the number of permutations of digits 1,2,3,4,4,5 and 6.
6! is the number of permutations of digits 1,2,3,{4,4},5 and 6.
We don't want to subtract all numbers where digits 4 appear side by side. That's why we must divide 6! by 2.
Finally, the probability is P=5^5(7!-6!/2)/7^7
Answer:
need more info
Step-by-step explanation:
Your correct it’s the first one
