Respuesta :
The relationships between the amount spent on books and the cost of
each book is a proportional relationship.
The correct responses are;
- [tex](a) \ \displaystyle \mathrm{The \ number \ of \ books \ Gaya \ buys \ is } \ \underline{\frac{48}{x} \ books}[/tex]
- [tex]\mathrm{(b) \displaystyle \underline{ \left(\frac{48}{x} -4 \right) \cdot \left(x + 2 \right) - 60 = x^2 - 5 \cdot x - 24 = 0}}[/tex]
Reasons:
The amount Gaya spends on books = $48
The cost of each book = $ x
(a) The expression in terms of x for the number of books Gaya buys is therefore;
Number of books Gaya buys × $ x = $48
Therefore;
- [tex]\displaystyle Number \ of \ books \ Gaya \ buys = \frac{\$48}{\$ x}[/tex]
(b) The amount Myra spends to buy books = $60
The cost of each book = $·(x + 2)
The number of books Myra buys = The number of books Gaya buys - 4
We have;
[tex]\displaystyle Number \ of \ books \ Myra \ buys = \frac{48}{x} - 4[/tex]
Which gives;
[tex]\displaystyle \mathbf{\left(\frac{48}{x} - 4 \right) \cdot \left(x + 2 \right)} = 60[/tex]
Using a graphing calculator, we get;
[tex]\displaystyle \frac{4 \cdot x^2 - 20 \cdot x - 96}{x} = 60[/tex]
4·x² - 20·x - 96 = 60·x
Which gives;
4·x² + 40·x - 60·x - 96 = 0
4·x² - 20·x - 96 = 0
x² - 5·x - 24 = 0
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https://brainly.com/question/17627037
