Respuesta :
Let
x------> is the number of weeks
y-----> is the amount of money
we know that
the equation that represent the situation is
[tex]y-10=-2(x-10)[/tex]
Step 1
Part a) How much did the bicycle cost?
Find the y-intercept of the linear equation
we know that
The y-intercept is the value of y when the value of x is equal to zero
so
For [tex]x=0[/tex]
substitute in the linear equation
[tex]y-10=-2(0-10)[/tex]
[tex]y-10=20[/tex]
[tex]y=\$30[/tex]
therefore
the answer part a) is
[tex]\$30[/tex]
Step 2
Part b) After how many weeks will Hugo finish paying for the bike?
Find the x-intercept of the linear equation
we know that
The x-intercept is the value of x when the value of y is equal to zero
so
For [tex]y=0[/tex]
substitute in the linear equation
[tex]0-10=-2(x-10)[/tex]
[tex]0-10=-2x+20[/tex]
[tex]2x=20+10[/tex]
[tex]x=30/2=15\ weeks[/tex]
therefore
the answer part b) is
[tex]15\ weeks[/tex]