Question

If measures of 3 angles of a quadrilateral are 65°, 95° and 45° then find the measure of the fourth angle.​

Answer 1

As we know,

As we know,Sum of all angles of a quadrilateral = 360⁰

Let L1= 65⁰, L2= 95⁰, L3= 45⁰ L4= ?

L1+L2+L3+L4=360⁰

65⁰+95⁰+45⁰+L4= 360⁰

205⁰+L4= 360⁰

L4= 360⁰-205⁰

L4= 155⁰

Hence, The measure of the the fourth angle, L4 = 155⁰

Answer 2

Given - 3 angles of the quadrilateral

Find - Measure of 4th angle

Solution - The fourth angle of the quadrilateral is 155°

Let the fourth angle of the quadrilateral be x. Now, as per the known fact, the sum of all the angles of the quadrilateral is 360°.

Representing the given information in a mathematical expression.

65 + 95 + 45 + x = 360

Performing addition to find the value of x.

205 + x = 360

x = 360 - 205

Performing subtraction to find the value of x.

x = 155

Hence, the fourth angle of the quadrilateral is 155°.