Point slope form: y - y1 = m (x - x1)
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first you need to find the slope(m) by using the slope formula (seen below)
y2 - y1
m= ---------
x2 - x1
9 - 15
m= ---------
1 - (-2)
-6
m= --------- = -2
3
then choose either one of the coordinates you'd like and plug it in.
Im gonna use (-2, 15)
(y - 15) = -2 (x - (-2))
or
(y - 15) = -2 (x + 2)
slope intercept form: y = mx + b
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you can use the slope formula to find that the slope(m) is -2
y = -2x + b
you can then plug in a coordinate to find b (the y-intercept)
I'll use (-2,15)
15 = -2(-2) +b
15 = 4 + b
-4 -4
---------
11 = b
in conclusion:
the slope(m) = -2
when (-2,15) is used
x = -2
y = 15
b = 11
standard form: ax + by = c
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using the same coordinate (-2,15)
-2a + 15b = c
Answer:
x=4
Step-by-step explanation:
Answer:
k = 10
Step-by-step explanation:
The sum of k terms of a geometric sequence with first term a1 and common ratio r is given by ...
... Sk = a1·(1 -r^k)/(1 -r)
For the given numbers, this is ...
... 118096 = 78732·(1 -(1/3)^k)/(1 -1/3)
Manipulating this to get the term containing k, we have
... 1 -(2/3)(118096/78732) = (1/3)^k
... 1/59049 = (1/3)^k
Taking logarithms, we get
... -log(59049) = -k·log(3)
... log(59049)/log(3) = k = 10
