Which of the following expressions is equal to cos125°?
-cos55°
cos55°
cos(-55)°

  -cos(55°)

Step-by-step explanation:

The reference angle for second-quadrant angle 125° is (180-125)° = 55°. The cosine is negative in the second quadrant, so the equivalent expression is ...

  cos(125°) = -cos(55°)

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Your calculator (in degrees mode) can help you sort this out.

1. 34

2. 268

3. x=14.4

step-by-step explanation:

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads