Step-by-step explanation:
by using similarity and enlargement
10/8 = 7+y/7
70=56+8y
8y=14
y= 7/4
10/8 = 5+x/5
50=40+8x
x = 8/10 = 4/5
<span>3x + y = 9 (I)
</span><span>y = –4x + 10 (II)
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
Pass the incognito "4x" to the first term, changing the signal when changing sides.
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simplify by (-1)
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
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
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
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<span><span>
</span></span><span>Substitute in equation (I) to find the value of "Y".
</span>3x + y = 9 (I)
3*(1) + y = 9
3 + y = 9
y = 9 - 3
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Answer:
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SAS since ∠RNM is congruent ∠PNQ by vertical angles which will give you the angle you need for SAS.
Multiply the number amount of cartridges by the number of books and add that tot he number of cartridges by the number of magazines.:
This needs to be either less than or equal tot he total cartridges she wants to use
40B + 30M ≤ 300
Do the same with pages:
200B + 80M ≤ 1200