Answer:
13
Step-by-step explanation:
The theorem is that for a line bisecting two parallel lines, the oposite angles are equal. Hence, you can formulate the equation 4x+18 = 7x-21, which solves to 13.
Quadrilateral and parallelogram
Squares are rectangles but rectangles are not squares b/c (not all sides are same length)
18x-16y=5
Subtract 18x from each side
-16y=-18x+5
Divide by -16
y=18/16x-5/16
y=9/8x-5/16 this one is with improper fractions
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<u>Step-by-step explanation:</u>
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