Using a system of equations, it is found that:
a)
[tex]b + w = 75[/tex]
[tex]15b + 20w = 1350[/tex]
b)
The solution is [tex]b = 30, w = 45[/tex]
c)
[tex]b + w = 75 \rightarrow 30 + 45 = 75 \rightarrow 75 = 75[/tex]
[tex]15b + 20w = 1350 \rightarrow 15(30) + 20(45) = 1350 \rightarrow 1350 = 1350[/tex]
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Item a:
Total of 75 hours, thus:
[tex]b + w = 75[/tex]
She was paid $15 an hour babysitting and $20 an hour dog walking. Earned a total of $1350, thus:
[tex]15b + 20w = 1350[/tex]
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Item b:
To solve for w, from the first equation:
[tex]b = 75 - w[/tex]
Replacing into the second:
[tex]15(75 - w) + 20w = 1350[/tex]
[tex]1125 - 15w + 20w = 1350[/tex]
[tex]5w = 225[/tex]
[tex]w = \frac{225}{5}[/tex]
[tex]w = 45[/tex]
Then, for b:
[tex]b = 75 - w = 75 - 45 = 30[/tex]
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Item c:
Replacing b and w into the equations:
[tex]b + w = 75 \rightarrow 30 + 45 = 75 \rightarrow 75 = 75[/tex]
[tex]15b + 20w = 1350 \rightarrow 15(30) + 20(45) = 1350 \rightarrow 1350 = 1350[/tex]
A similar problem is given at https://brainly.com/question/17096268