I don't understand how to do this

20 degrees

Step-by-step explanation:

You know that the three angles will add up to 180 degrees, so you can make an equation:

3x (angle 1) + 2x + 20 (angle 2) + 5x - 40 (angle 3) = 180

3x + 2x + 20 + 5x - 40 = 180

Then, solve

combine like terms

10x - 20 = 180

add 20 to both sides

10x = 200

divide both sides by 10

x = 20 degrees

b: |12 – x| ≤ 0.25

step-by-step explanation:      

let x be the possible lengths in inches, of the ribbons jaime cut.

we have been given that jaime is cutting strips of ribbon for a project. he tries to cut each piece to be 12 inches long, but sometimes he cuts it too long or too short by as much as 0.25 inch.  

we can represent this information in an inequality as:

by the definition of absolute value function we will get,

upon combining our inequalities we will get,

therefore, the inequality   describes all the possible lengths (x), in inches, of the ribbons jaime cut.

step-by-step explanation:

$3720

step-by-step explanation:

taxable income = $31000

as per the 2018-2019 us tax bracket, the tax rate is 12% for an individual whose taxable income is between $9,526 to $38,700.

so, the tax to be paid by him = 12% of 31000

= 0.12 * 31000     [12% converted to decimal as 0.12]

= $3720