Simple Proof:
a) In the image, we know that ABCD is a parallelogram and that means opposite angel measures should be the same. We know that angel DCB is made up by angel 1 and 2, and angel DAB and DCB are equal and angel DAB is made up by angel 1 and <em>x</em>. So now we can conclude that angel <em>x</em> is equal to angel 2.
b) According to the definitions of a parallelogram, opposite angel measures have to be the same, while AECF have angle 1 to angel 1 and angel 2 to angel 1. We can conclude that AECF is <u>NOT</u> a parallelogram. (Sorry, you didn't give me the full question so some information remains unclear. )
There's only information to answer question C.
We can only know that 32 marbles were chosen. (yellow and black)
Why?
To answer the first two questions (a and b), we need to know the total number of marbles, so, we can only answer the last question (c).
We know that 7/10 of the 20 yellow marbles were chosen.
So, calculating we have:

Also, we know that 18 black marbles were chosen, so, the total of marbles chosen is equal to 32 (yellow marbles and black marbles)

Have a nice day!
Answer:
6,346
Step-by-step explanation:
add add multiply and add
Answer:
Since there are 2 sides, a front & back, and a top & bottom, you must find the surface area of each of those 3 surfaces and multiply by 2.
Step-by-step explanation:
The formula would be:
Top & Bottom - 5 × 4 (multiply by 2 for top AND bottom)
Front & Back - 5 × 7 (multiply by 2 for front AND back)
Sides - 4 × 7 (multiply by 2 for BOTH sides)
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Once you find the 3 surface areas, add the areas all together for the total. (I did not show the answer because that is for you to do on your own.)
Ex. Top & Bottom + Front & Back + Sides
Step-by-step explanation:
x = 2 is, as you can see, parallel to the y-axis.
perpendicular to this (= crosses the original line in an angle of 90 degrees) is then a line parallel to the x-axis.
that means y is constant. all points on that line will have the same y value.
and we know one point already : (3, -2)
so all points of the perpendicular line will have y = -2
and that is the equation of the perpendicular line :
y = -2