SkinnyMinnie20:

ABCD is a parallelogram. Find the measure of angle A.

8 months ago
SkinnyMinnie20:

|dw:1508374996187:dw|

8 months ago

Remember that consecutive angles are supplementary. In this case, C + D = 180 degrees.

8 months ago
SkinnyMinnie20:

i tried that but i did not get the answer

8 months ago

One of our other parallelogram rules tell us that opposite angels are congruent.

8 months ago

The question is asking for the measure of angle A. What angle, if we were to solve for, would give us the same angle as angle A?

8 months ago
SkinnyMinnie20:

angle c

8 months ago

Correct

8 months ago

Show me your work for solving those angles

8 months ago
SkinnyMinnie20:

how would I do that. cause i did it three ways and neither way is working

8 months ago

I'll show you.

8 months ago

As per what I said earlier. "In this case, C + D = 180 degrees." Angle C = 8x - 8 Angle B = 17x + 13 $17x + 13 + 8x - 8 = 180$ Like terms $25x + 5 = 180$ Subtract five from both sides $25x = 175$ Divide both sides by 25 $x = 7$

8 months ago

Where do we go from here?

8 months ago

Or actually, is that what you were getting earlier?

8 months ago
SkinnyMinnie20:

okay I did it that way but got some numbers mixed up

8 months ago

It happens :) So what do we do next?

8 months ago
SkinnyMinnie20:

would we plug in x

8 months ago

In which expression

8 months ago

Keeping in mind, Angle A is what we are trying to solve for.

8 months ago
SkinnyMinnie20:

(8x-8)

8 months ago

Correct

8 months ago
SkinnyMinnie20:

so angle c is in congruent to angle a

8 months ago
SkinnyMinnie20:

8 months ago

Correct again!

8 months ago