Question

In right triangle DEF, ∠E is a right angle, m∠D=26∘, and DF=4.5.
sin26∘≈0.44
cos26∘≈0.90
tan26∘≈0.49
What is the measurement of EF

Answer 1

Answer:

The measurement of EF is 1.98 units

Step-by-step explanation:

In Δ DEF

∵ m∠E = 90°

∴ FD is the hypotenuse of the triangle

∵ m∠D = 26°

∵ EF is opposite to angle D

- We can use the sine ratio to find it

∵ sin D = $\frac{EF}{FD}$ ⇒ (opposite side / hypotenuse)

∵ FD = 4.5 units

∴ sin(26) = $\frac{EF}{4.5}$

- Multiply both sides by 4.5

∴ 4.5 sin(26) = EF

∵ sin 26° ≈ 0.44

∴ 4.5(0.44) = EF

∴ 1.98 = EF

The measurement of EF is 1.98 units