We have:

Then we use trigonometric identities to change the negative sign of the trigonometric functions, so:

We clear f(x):

we simply what we can:

Thus, the correct answer is;
Answer:
Step-by-step explanation:
Answer:
y = -5/9x + 4.1
(try doing this yourself first with different points to make sure this is the right answer, because im to lazy to check myself but ill try checking D:)
Step-by-step explanation:
first you have to find the slope . to do this use the equation y2 - y1/ x2 - x1
so write as -2 - 3/ -7 - 2 is equal to -5/-9
so now write y = -5/9x + b
we must now find the y-intercept so substitute one of the points given. lets substitute 2,3 it looks easier. So it will look like 3 = -5/9(2) + b
3 = -5/9(2) + b
3 = -10/9 + b
b = 3 + 10/9
b = 4.111111
um just round to the tenth place
Let the base of the ladder be x ft and the extension be y ft.
"when fully extended, a ladder is 28 feet in length."
means: x+y=28
"<span>the extension is 4 feet shorter than the base</span>"
means: y=x-4, that is x-y = 4, (taking y to the side of x, and -4 to the other side of x and y)
thus, we have the system of equations:
1) x+y= 28
2) x-y=4
adding the 2 equations, we have:
(x+y)+(x-y)=28+4
2x=32
x=32/2=16
x+y=28, so 16+y=28, thus y=12
Answer: Base: 16, Extension 12