Question

if PQ//ST, the value of x is PQR = 40⁰, QRS = 15⁰ and RST = X⁰​

Answer 1

Answer:

(c)155

Step-by-step explanation:

Extend line ST to the left such that it intersects QR.

Let's name it A

Now, PQR=40

        QAS=40 as PQ//ST so they are alt.interior angles.                  ....1

We can now see that ARS form a triangle

=angle ARS+RAS+RSA=180    (sum of angles of a triangle).             ....2

=angle RAS+QAS=180            (angles formed in a straight line).

=RAS=180-40=140                   (as per ...1).

140+15+RSA=180                     (....2)

RSA=180-155=25

angle RSA+RST=180               (angles formed in a straight line).

x=180-25=155                          (RST=x)