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Use the cosine ratio to find m∠D.
f≈6.1
m∠D≈ 64.8^(∘)
m∠E≈ 25.2^(∘)
First, let's draw the measurements from the exercise on a right triangle to visualize the given information.
We will find the missing measures one at a time. In this case, this means that we want to find f, m∠D, and m∠E.
We can find the hypotenuse f by using the Pythagorean Theorem.
d= 12, e= 10
Calculate power
Add terms
sqrt(LHS)=sqrt(RHS)
Rearrange equation
Use a calculator
Round to 1 decimal place(s)
Let's add this value to our diagram.
We can find m∠D by using the cosine ratio. The cosine of ∠D is the ratio of the length of the leg adjacent ∠D to the length of the hypotenuse. cos D=Adjacent/Hypotenuse ⇒ cos D=2.6/6.1 By the definition of the inverse cosine, the inverse cosine of 2.66.1 is the measure of ∠D. To find it, we can use a calculator.
Use a calculator
Round to 1 decimal place(s)
To find m∠E, recall that the acute angles of a right triangle are complementary. Therefore, m∠D and m∠E add to 90^(∘). m∠D+m∠E=90^(∘) Now,we can substitute the approximated measure of ∠D in our equation and find the measure of ∠E. 64.8^(∘) +m∠E≈ 90^(∘) ⇔ m∠E≈ 25.2^(∘)