Answer:
-¹²/₅
Step-by-step explanation:
Let cos a = -⁵/₁₃
Then tan a = sin a/cos a
= [√(1 - cos²a)]/cos a
= {√[1 - (-⁵/₁₃)²]}/(-⁵/₁₃)
= -[√(1 - ²⁵/₁₆₉)] × ¹³/₅
= -[(√(¹⁴⁴/₁₆₉ )] × ¹³/₅
= -¹²/₁₃ × ¹³/₅
= -¹²/₅
tan(arccos (-⁵/₁₃)) = -¹²/₅
The diagram shows the 2nd quadrant of a circle with radius 13, cos a = -⁵/₁₃, and tan a = ¹²/₍₋₅₎ = -¹²/₅.
Answer:
x = 29
Step-by-step explanation:
I think this because they give you 78 degrees. The angle across from it (3x - 9) must equal 78 degrees as well. So solve as (3x - 9) = 78. 78 + 9 is 87. 87 divided by 3 is 29.
Hope it helps and is correct!
Set up the equation so m<HCB + m<DCH = m<DCB
2x + 100 + 60 = x + 170
2x+ 160 = x +170
-x -x
x + 160 = 170
- 160 -160
x = 10
2x - 4 < y. graph it. y > 2x - 4. boom answer