Question

The measures of the three angles of a quadrilateral are 65, 75 and 85. The measure of the fourth angle is 1 point 65 75 85 135

Answer 1

Answer:

135

Step-by-step explanation:

let 4th angle = a

the sum of the angles of quadrilateral = 360

=> 65+75+85+a = 360

=> 225+a = 360

=> a = 360-225 = 135

Answer 2

Given - Three angles

Find - Fourth angle

Solution - Let the fourth angle be x. As per the known fact, the sum of interior angles of quadrilateral is 360°. Representing the information in mathematical expression -

65 + 75 + 85 + x = 360

Performing addition on Left Hand Side

225 + x = 360

Shifting 225 to Left Hand Side

x = 360 - 225

Performing subtraction

x = 135

Hence, the value of fourth angle is 135.