Have in mind the following properties:
- Opposite sides are congruent.
- Opposite angles are congruent
- Consecutive angles are supplementary
- The diagonals of a prallelogram bisect each other.
- Each diagonal of a parallelogram separetes it into two congruent triangles.
So
7)
[tex]2x - 5 = 5x -17\\12 = 3x\\x=4\\\\5y + 2 = y +22\\4y = 20\\y =5[/tex]
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8)
[tex]7y - 37 = 2y +10\\5y = 47\\y =47/5 = 9.4\\\\( 2y + 10) + (4x + 40) = 180\\2y + 4x = 130\\2(47/5) + 4x = 130\\4x = 130 -2 (47/5) \\x= 27.8[/tex]
