Does anyone know what this is ?

9514 1404 393

  x = 2

Step-by-step explanation:

The mnemonic SOH CAH TOA reminds you of the relations between trig functions and angle.

  Tan = Opposite/Adjacent

  tan(θ) = y/x

  Sin = Opposite/Hypotenuse

  sin(θ) = y/4

The given relation is ...

  tan(θ) = 2·sin(θ)

  y/x = 2(y/4)

  2 = x . . . . . . . multiply by (2x/y)

Additional comment

Then the angle can be found from the relation ...

  Cos = Adjacent/Hypotenuse

  cos(θ) = x/4 = 2/4 = 1/2

  θ = arccos(1/2) = 60°

and the value of y is ...

  y = 4·sin(60°) = 2√3

∠1≅∠2 by the alternate exterior angles theorem.

step-by-step explanation:

given, a ∥ b and ∠1 ≅ ∠3 .we have to prove that e ∥ f

we know that ∠1≅∠3 and that a || b because they are given. we see that by the alternate exterior angles theorem. therefore, ∠2≅∠3 by the transitive property. so, we can conclude that e || f by the converse alternate exterior angles theorem.

we have to fill the missing statement.

transitivity property states that if a = b and b = c, then a = c.

now, given ∠1≅∠3 and by transitivity property ∠2≅∠3 .

hence, to apply transitivity property one angle must be common which is not in result after applying this property which is ∠1.

the only options in which ∠1 is present are ∠1 and ∠2, ∠1 and ∠4

∠1 and ∠4 is not possible ∵ after applying transitivity we didn't get ∠4.

hence, the missing statement is ∠1≅∠2.

so, ∠1≅∠2 by the alternate exterior angles theorem.