Its 8
not sure how to show the work but drew a pic and its 8
Answer:
13.36
Step-by-step explanation:
18.60 - 5.24
=>13.36
<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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<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

Answer:

81 + 70 + x = 3(73)
first multiply 3(73)
81 + 70 + x = 219
combine like terms
151 + x = 219
subtract 151 from both sides
x = 68
Joaquin needs to score a 68 on her next test to maintain an average of 73.