Are these correct? ILL MARK YOU BRAINLIEST

Yes

Step-by-step explanation:

1) Cos 300 = Cos (360 - 60) = Cos 60    {Cos 360 - theta = Cos theta}

                                              = 1/2

Sin 300 = Sin (360 - 60) = -Sin 60 =

3) 3π/4 = 3*180/4 = 135

Cos 135 = Cos (90 + 45) = -Cos 45 =

Sin 135 = Sin (90 + 45) = Sin 45 =

step-by-step explanation:

-7

step-by-step explanation:

x^2 + 18x + 74 = (x + 9)^2 - 81 + 74

= (x + 9)^2 - 7.

so q = -7.