Given:
Plan 1:
Charge for each minute = $0.19
Plan 2:
Monthly fee = $28
Charge each minute = $0.15
Let's determine when the costs of the two plans will be equal.
We have the following:
Equation for plan 1:
y = 0.19x
Equation for plan 2:
y = 0.15x + 28
Where x represents the number of minutes.
Now, to find when they will be equal, eliminate the equivalent sides y, then equate both expressions.
![0.19x=0.15x+28](https://img.qammunity.org/2023/formulas/mathematics/college/axzieinkf959m0u8uz9cmdy20130jt0vxv.png)
Let's solve for x.
Subtract 0.15x from both sides:
![\begin{gathered} 0.19x-0.15x=0.15x-0.15x+28 \\ \\ 0.04x=28 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/hoeo1o7sijawwh4lvxy00r795s4qmx1ifd.png)
Divide both sides by 0.04:
![\begin{gathered} (0.04x)/(0.04)=(28)/(0.04) \\ \\ x=700 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/y44e95qo41zk03nel4and0u2aolaijxk7n.png)
Therefore, the two costs will be equal at 700 minutes.
ANSWER:
700 minutes