Question

Please and thank you

Answer 1

Question:

Solution

Notice that the graph is a line, and the equation for a line can be written as:

$y\text{ = mx+b}$

or

$f(x)\text{ = mx+b}$

where m is the slope of the line, and b is the y-coordinate of the y-intercept of this line (where x = 0). In this case, notice that when x = 0 then y = 0, so b = 0. Then, we only need to find the slope of the line. By definition, the slope of a line is given by the following equation:

$m\text{ = }\frac{Y2-Y1}{X2-X1}$

where (X1,Y1) and (X2,Y2) are any two points on the line. Take for example the points:

(X1,Y1) = (1,9)

(X2,Y2) = (2,18)

then, the slope of the given line would be:

$m\text{ = }\frac{18-9}{2-1}\text{ = }9$

thus, the equation for the given line (the relationship between the number of pounds and price) is:

$f(x)\text{ = 9x}$

where x is the pounds and f(x) is the price for a given pound. Thus, the unit price of steak is:

$f(1)\text{ = 9.1 = 9}$

then the correct answer is A: $9 / 1lb