Perpendicular lines have slopes that are negative reciprocals. example: line a has a slope of 2/3, line b has a slope if -3/2 if they are perpendicular.
In slope-intercept form, we have these values (y = mx + b):
m = slope
b = y-intercept
Change the equation from standard form to slope-intercept form.
-9x + 7y = 28
-9x + 9x + 7y = 28 + 9x
7y = 28 + 9x
7y/7 = 28/7 + 9x/7
y = 4 + 9/7x
y = 9/7x + 4
Therefore, the y-intercept is 4.
Best of Luck!
Given
- f(n) values for n=1,2,3,4
- possible candidates for the function
Solution:
Method: Evaluate some of the values, for each function. A function with ANY value not matching the given f(n) values will be rejected.
N=1, f(n)=4
f(1)=4-3(1-1)=4
f(1)=4+3^(1+1)=4+3^2=4+9=13 ≠ 4 [rejected]
f(1)=4(3^(n-1))=4(3^0)=4
f(1)=3(4^(n-1))=3(4^0)=3*1=3 [rejected]
N=2, f(n)=12
f(1)=4-3(2-1)=4-3(1)=1 ≠ 12 [rejected]
[rejected]
f(1)=4(3^(2-1)=4*3^1=4*3=12
[rejected]
Will need to check one more to be sure
N=3, f(n)=3
[rejected]
[rejected]
f(3)=4(3^(n-1))=4(3^(3-1))=4(3^2)=4*9=36 [Good]
[rejected]
Solution: f(n)=4(3^(n-1))
I think it means grater or less ? Or positive or negative?