Respuesta :
To solve this problem we can find the linear equation that relate the hours and the price.
We know Ja'niya charges $31.25 for 5 hours and $50 for 8 hours.
We call x the hours and y the price, and we have the points (5, 31.25) and (8, 50). The equation is:
[tex]\begin{gathered} P_1=(x_1,y_1)=(5,31.25),P_2=(x_2,y_2)=(8,50) \\ y-y_1=\frac{(y_2-y_1)}{(x_2-x_1)}(x-x_1) \\ y-31.25=\frac{(50-31.25)}{(8-5)}(x-5) \\ y=\frac{18.75}{3}(x-5)+31.25 \\ y=\frac{18.75}{3}x-5\cdot\frac{18.75}{3}+31.25 \\ y=\frac{18.75}{3}x-31.25+31.25 \\ y=\frac{18.75}{3}x \end{gathered}[/tex]To find how much she charges for 3 hours we have to replace x for 3 in the equation above:
[tex]\begin{gathered} \text{For x=3 hours:} \\ y=\frac{18.75}{3}\cdot3=18.75 \end{gathered}[/tex]So, she charges $18.75 for 3 hours.
