Item 4 The sum of the angle measures of the polygon is 540°. Write and solve an equation to find the value of x. An equation is =540. The solution is x= .

Let's set the sum of the angle measures equal to 540 degrees.

139 + 3x + 5x - 10 + 10x - 9 + 3x = 540

Let's combine like terms.

21x + 120 = 540

Subtract 120 from both sides.

21x = 420

Divide both sides by 21

x = 20

step-by-step explanation:

descending order means to order the polynomials from the term with the largest exponent to the term with the smallest exponent.  

therefore, the correct answer is d.  

explanation:

infrared radiation has wavelength in the range between 700 nm and 1 mm. lets' convert these values into scientific notation, keeping in mind that:

let's start from the lower value, we have:

(we moved the dot two places to the left, so we increased the exponent by 2 units, from -9 to -7)

the higher value is:

so, the range of wavelength of infrared radiation is: