<span>Angle 7 and 5 are vertical angles, so they're equal.
Angles 7 and 8 are supplementary, so they have to add up to 180.
2x + 15 + 3x = 180
Solve for x, then plug it into the expression for angle 7 to get you answer</span>
Answer:
Step-by-step explanation:
The given trigonometric identity is .
Jana has to recall that, the cosine function is an even function.
For that matter, .
Jana has to apply this property by substituting for in the given identity to obtain,
.
Note that, the sine and the tangent functions are odd functions
Answer:
The answer is -20.6
Step-by-step explanation:
-5x-25=78
-5x+25-25=78+25
-5x=103
-5x/-5=103/-5
x=-20.6
1/9=0.11111.....
so the correct option is (a).
