Three interior angles of a quadrilateral measure 55° 117° and 120° what is the measure of the fourth interior angle. 68 degrees
78 degrees
88 degrees
98degrees

Given:

Measure of three interior angles of a quadrilateral is 55° , 117° and 120°

Step-by-step explanation:

Let the fourth interior angle be 'x'

The Interior Angles of a Quadrilateral add up to 360°

x = 10.1

step-by-step explanation:

all of the angles of a tirangle add up to 180º

180 - 65 = 115 (since we already know the value of one angle)

(2x + 7) + (8x + 7) = 115

(combins like terms) 10x + 14 = 115

(isolate the variable subtract 14 from both sides): 10x = 101

(find the variable divide both sides by 10): x = 101/10

x = 10.1