Cos(θ) = -20/√((-20)^2 +(-21)^2)
.. = -20/-√841 . . . . . . . . . . . . . . . . . θ is a 4th-quadrant angle, so cos(θ) > 0
.. = 20/29
The value of the cosine is 20/29.
We know that y is equal to x-2. We can just substitute x-2 for y since y is equal to it.
10x- 9(x-2)=24
Distribute.
10x- 9x+18= 24
x+18= 24
Subtract 18 on both sides.
x= 6
Now, plug in x.
y= (6)-2
y= 4
We can check this to see if this works:
4= 6-2, 4=4
10(6)- 9(4)= 24
60-36= 24, 24=24
x=6 and y=4
I hope this helps!
<em>~kaikers</em>