Angles α and β are angles in standard position such that: α terminates in Quadrant III and sinα = - 5/13 β terminates in Quadrant II and tanβ = - 8/15 Find cos(α - β)

-220/221
-140/221
140/221
220/221

140/221.

Step-by-step explanation:

For the triangle containing  angle α:

The adjacent side is -√(13^2-5^2) = -12.

For the triangle containing angle β:

Hypotenuse = √(-8)^2 + (15)^2) =  17.

cos(α - β) = cos α  cos β   + sin α   sin β

= ((-12/13) * (-15/17) + (-5/13)* (8/17)

= 180/221 + - 40/221

= 140/221.

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m

the formula for the equation of a circle is (x – h)2+ (y – k)2 = r2, where (h, k) represents the coordinates of the center of the circle, and r represents the radius of the circle. if a circle is tangent to the x-axis at (3,0), this means it touches the x-axis at that point.