Question

Given: mTP= 70°,m∠EPT = 54° Find: Angles of △SPT

Answer 1

Answer:

The Angles of △SPT are

$m\angle STP=35\°$  

$m\angle SPT=126\°$

$m\angle PST=19\°$

Step-by-step explanation:

step 1

Find the measure of angle PET

we know that

The inscribed angle is half that of the arc it comprises.

$m\angle PET=\frac{1}{2}(arc\ PT)$

substitute the given values

$m\angle PET=\frac{1}{2}(70\°)$

$m\angle PET=35\°$

step 2

Find the measure of angle PTE

we know that

The sum of internal angles of a triangle must be equal to 180 degrees

In the triangle PET

$m\angle PET+m\angle EPT+m\angle PTE=180\°$

substitute the given values

$35\°+54\°+m\angle PTE=180\°$

$m\angle PTE=180\°-89\°=91\°$

step 3

Find the measure of angle STP  

we know that

The inscribed angle is half that of the arc it comprises.

$m\angle STP=\frac{1}{2}(arc\ TP)$

substitute the given values

$m\angle STP=\frac{1}{2}(70\°)=35\°$

step 4

Find the measure of angle SPT

we know that

$m\angle SPT+m\angle EPT=180\°$ ----> by supplementary angles

$m\angle SPT+54\°=180\°$

$m\angle SPT=180\°-54\°=126\°$

step 5

Find the measure of angle PST

we know that

The sum of internal angles of a triangle must be equal to 180 degrees

In the triangle SPT

$m\angle STP+m\angle SPT+m\angle PST=180\°$

substitute the given values

$35\°+126\°+m\angle PST=180\°$

$m\angle PST=180\°-161\°=19\°$