Find the unknown angle measure by solving for the given variable

answer choices are: 125, 35, 40, and 140.

A straight line is 180°. So you can do:

(15x - 4) + (5x - 8) = 180  Simplify

20x - 12 = 180

20x = 192    Find the value of x

x = 9.6

m∠ABD = 15x - 4      Plug in x = 9.6

m∠ABD = 15(9.6) - 4 = 144 - 4 = 140°

m∠DBC = 5x - 8   Plug in 9.6

m∠DBC = 5(9.6) - 8 = 48 - 8 = 40°

first option

a function is a relation in which an input is paired with exactly one output.

so, let's find the right answer.

in our first option, our inputs are january, february, and march. the outputs are 30, 28, and 25. each input has it's own output. this is correct!

our second option we know is incorrect, because ms. valverade has two outputs, dogs and cats. this is not a function.

our third option is incorrect as well. the yellow square has two ouputs, the square and the triangle.

lastly, in our fourth option, we see the number 7 two times with a different output. therefore, this is not a function.

remember: each input must be paired with only one output!

step-by-step explanation:

∆abc has the points a(1, 7), b(-2, 2), and c(4, 2) as its vertices. formed with the point d(1, 2) as its third vertex, then ∆abd is triangle.