Lines k and l are parallel, and the measure of angle abc is 19 degrees

a. explain why the measure of angle ecf is 19 degrees

b. what is the measure of angle bcd? explain.

A. Because the measure of the angle is and the angles  and are Vertical angles. Therefore, they are congruent ( )

B.  

Step-by-step explanation:

You can observe in the figure that the parallel lines and are intersected by a another line (this is a transversal).

Let's begin with PART B:

Observe that the angles and are located inside the parallel lines and they alternate sides of the transversal. Therefore, we can determine that these angles are "Alternate Interior Angles".

Since the lines and are parallel, we know that the Alternate Interior Angles are congruent. Then:

Now we can solve the PART A.

Observe the figure.

Since the angle  and the angle share the same vertex, they are "Vertical angles" and, therefore, they are congruent:

14

step-by-step explanation:

14 x 3 = 42

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116