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Given STU and DEF what is the m

Given STU and DEF what is the m-example-1
User Junya Kono
by
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1 Answer

7 votes

Answer:

m<E = 105°

Step-by-step explanation:

The ratio of the corresponding side lengths of ∆STU and ∆DEF are equal. That is:


(ST)/(DE) = (TU)/(EF) = (SU)/(DF) = (15)/(6) = (10)/(4) = (20)/(8) = 2.5.

According to similarly theorem, if two ∆s are similar, the ratio of their corresponding lengths would be the same. Therefore, ∆STU is similar to ∆DEF.

Since ∆STU ~ ∆DEF, their corresponding angles are congruent. That is:

<S ≅ <D, this means both are 29° each.

<T ≅ <E, this means they are both equal

<U ≅ <F. this means both are 46° each.

Thus:

m<E = 180 - (m<D + m<F) (sum of ∆)

m<E = 180 - (29 + 46) (substitution)

m<E = 180 - 75

m<E = 105°

User Ben Straub
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5.3k points