<span>−8x+7y=25 is already in standard form, altho some people would prefer to re-write it as
</span><span>−8x+7y-25 = 0.
You have shared 4 equations here. Next time, please separate them with commas or semi colons, or type just 1 equation per line, for increased clarity. Thanks.</span>
Answer: 
Step-by-step explanation:



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Answer- 
Answer:
1. -29/156 2. 38/45 3. 29/45 4. 113/24 or about 4.7 5. 457/1, 914/2, 1371/3
Step-by-step explanation:
3/13 - 5/12 can be simplified to 36/156 - 65/156. Subtract this and you get -29/156
4/9 + 2/5 can be simplified to 20/45 + 18/45. Add this and you get
38/45
5/8 - 2/9 can be simplified to 45/72 - 16/72. Subtract this and you get
29/45
3 1/2 + 2 5/12 can be first made irrational to 7/2 + 29/24. This can be simplified to 84/24 + 29/24
113/24 or about 4.7
Not sure about the 457, but to convert it, you multiply it by whatever denominator you have. For example
1x457 = 457/1
2x457 = 914/2
And finally 3x457 = 1371/3
Answer:
A=πr2
Step-by-step explanation:
Answer: G
Step-by-step explanation: the rate of change is constant, making it a proportional relationship