Check below, please.
1) Considering the given problem, we can write out the following answering those questions.
2) Let's define the variable as x
Matt:
the cost for Matt's job is modeled by 2x+15
Since those $15 dollars are fixed and he charges $2 per dog.
Angela:
Her earnings are modeled by 3x+5
Since those $5 dollars are fixed and he charges $3 per dog.
Equation
We can write the following expression to get to know the number of animals that makes no difference picking Angela or Matt:
2x+15 =3x+5
Work
[tex]\begin{gathered} 2x+15=3x+5 \\ 2x-3x=5-15 \\ -x=-10 \\ x=10 \end{gathered}[/tex]So, for 10 dogs there is no difference whether Angela or Matt is taking care for the cost will be the same.