(0,5)(4,0)
slope = (0 - 5) / (4 - 0) = -5/4
y = mx + b
slope(m) = -5/4
use either of ur sets of points....(0,5)...x = 0 and y = 5
now we sub and find b, the y int
5 = -5/4(0) + b
5 = b
so ur equation is : y = -5/4x + 5...but we need it in standard form...
y = -5/4x + 5
5/4x + y = 5....multiply everything by common denominator of 4
5x + 4y = 20 <== standard form of Ax + By = C
Answer:
f) a[n] = -(-2)^n +2^n
g) a[n] = (1/2)((-2)^-n +2^-n)
Step-by-step explanation:
Both of these problems are solved in the same way. The characteristic equation comes from ...
a[n] -k²·a[n-2] = 0
Using a[n] = r^n, we have ...
r^n -k²r^(n-2) = 0
r^(n-2)(r² -k²) = 0
r² -k² = 0
r = ±k
a[n] = p·(-k)^n +q·k^n . . . . . . for some constants p and q
We find p and q from the initial conditions.
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f) k² = 4, so k = 2.
a[0] = 0 = p + q
a[1] = 4 = -2p +2q
Dividing the second equation by 2 and adding the first, we have ...
2 = 2q
q = 1
p = -1
The solution is a[n] = -(-2)^n +2^n.
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g) k² = 1/4, so k = 1/2.
a[0] = 1 = p + q
a[1] = 0 = -p/2 +q/2
Multiplying the first equation by 1/2 and adding the second, we get ...
1/2 = q
p = 1 -q = 1/2
Using k = 2^-1, we can write the solution as follows.
The solution is a[n] = (1/2)((-2)^-n +2^-n).
I don’t really know….but nice computer :)
If you already have an equation, all you have to do is locate the slope and look after it. But if it's in a graph, it's where the line is crossing the y-axis.
An example of the equation would be
y=2x+3
y=mx+b
2 would be m which is slope
and 3 would be b which is the y-intercept
50 mph for 3 hours = 150 miles
70mph for 2.5 hours = 140 + 35 = 175
175 miles - 150 miles = 25 miles
