Question

The sum of the angle measures of a quadrilateral is 360°. Write and solve an equation to find the value of X.​

Answer 1

1). x° + 100° + 120° + 100° = 360°

2). x = 40

Explanation:

Formula for the sum of the interior angles of a polygon =
`(n-2)* 180`

Where n = number of sides of the polygon

From the picture attached,

For n = 4,

Sum of the interior angles of the given polygon = (4 - 2) × 180°

= 360°

Therefore, equation for the sum of interior angles will be,

x° + 100° + 120° + 100° = 360°

x° + 320° = 360°

x° = 360° - 320°

x° = 40°