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riadik2000 [5.3K]
3 years ago
15

Solve the system of linear equations by substitution. Check your solution.

Mathematics
1 answer:
bearhunter [10]3 years ago
8 0
1. X+2=3x-4
6=2x
x= 3

2. y= 8-x
8-x = 3x+4
4= 4x
X= 1

3. -2x +3(2x+7)=9
-2x + 6x + 21 = 9
4x = -12
x= -3
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Xy=30
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2 years ago
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Rasek [7]

Answer:

The percent markup is, \simeq 60.89 % .

Step-by-step explanation:

A pair of shoes cost $ 22.99 to make, the local store sells them for $ 36.99.

So, the increased value for each pair of shoes,

= $ (36.99 - 22.99)

=$ 14

So, the percent markup is,

\frac {14 \times 100}{22.99} %

\simeq 60.89 %

7 0
3 years ago
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