Please help will leave good review and brainliest!
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Answer:
Step-by-step explanation:
For a parallelogram the diagonals (and half diagonals are equal. So we can say
3m=m+8
2m=8
m=4
And we can also say that
3m+m+8=2n-1+9
4m+8=2n+8
4m=2n
2m=n, and since we know m=4
n=2(4)
n=8
So m=4 and n=8