Angles α and β are the two acute angles in a right triangle. Use the relationship between sine and cosine to find the value of β if β < α.sin(3x - 27) = cos(5x + 5)
A. 14
B. 15
C. 75
D. 76

Respuesta :

Answer:

[tex]\boxed{\boxed{\beta=15^{\circ}}}[/tex]

Step-by-step explanation:

As given as ∠α and ∠β are the two acute angles in a right triangle.

So,

[tex]\Rightarrow \alpha+\beta=90^{\circ}[/tex]

[tex]\Rightarrow \alpha=90^{\circ}-\beta[/tex]

[tex]\Rightarrow \sin \alpha=\sin(90^{\circ}-\beta)[/tex]

[tex]\Rightarrow \sin \alpha=\cos \beta[/tex]

Also given as,

[tex]\sin(3x - 27) = \cos(5x + 5)[/tex]

Then between (3x-27) and (5x+5), one is α and the other one is β.

And the sum of both the angles are 90°. So,

[tex]\Rightarrow (3x - 27)+(5x + 5)=90[/tex]

[tex]\Rightarrow 8x - 22=90[/tex]

[tex]\Rightarrow 8x=90+22=112[/tex]

[tex]\Rightarrow x=14[/tex]

Then the measurement of the two angles are,

[tex]3x - 27=3(14) - 27=15^{\circ}\\\\5x + 5=5(14) + 5=75^{\circ}[/tex]

As β < α, so β=15°