All Exams Test series for 1 year @ ₹349 only
Question

In a triangle PQR, if $\angle P + \angle R = 150^\circ$ and $\angle P + 3\angle Q = 170^\circ$, then $\angle P$ is equal to :

The correct answer is
$80^\circ$

Triangle Angle P Calculation

We are given a triangle PQR with the following conditions:

  • $ \angle P + \angle R = 150^\circ $ (Equation 1)
  • $ \angle P + 3\angle Q = 170^\circ $ (Equation 2)

We know the sum of angles in any triangle is $180^\circ$. Therefore:

$ \angle P + \angle Q + \angle R = 180^\circ $

Step 1: Find Angle Q

Substitute Equation 1 into the triangle angle sum property:

$ ( \angle P + \angle R ) + \angle Q = 180^\circ $ $ 150^\circ + \angle Q = 180^\circ $

Solve for $ \angle Q $:

$ \angle Q = 180^\circ - 150^\circ $

$ \angle Q = 30^\circ $

Step 2: Find Angle P

Now, use Equation 2 and the value of $ \angle Q $ we found:

$ \angle P + 3\angle Q = 170^\circ $

Substitute $ \angle Q = 30^\circ $:

$ \angle P + 3(30^\circ) = 170^\circ $

$ \angle P + 90^\circ = 170^\circ $

Solve for $ \angle P $:

$ \angle P = 170^\circ - 90^\circ $

$ \angle P = 80^\circ $

Thus, $ \angle P $ is $80^\circ$.

Was this answer helpful?

Important Questions from Geometry (Notes)

  1. A 6 cm long chord of a circle is at a distance of 4 cm from the centre of the circle. Find the distance of 8 cm long chord of the same circle from the centre.
  2. PQR is a triangle. The bisectors of the internal angle $\angle Q$ and external angle $\angle R$ intersect at M. If $\angle QMR = 40^\circ$, then $\angle P$ is :
  3. A $2\text{ m}$ long ladder is to reach a wall of height $1.75\text{ m}$. The largest possible horizontal distance of the ladder from the wall could be
  4. Three-quarters of a circle is shown in the figure; OA and OB are two radii perpendicular to each other. C is a point on the circle.

    What is angle ACB?

  5. In the context of tiling a plane surface, which of the following polygons is the odd one out?

Need Expert Advice?

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App