Question

how many cakes does reid need to sell in order to have just $500 left to raise?

submit

50 cakes

60 cakes

70 cakes

30 cakes

this graph shows how the amount of money left to raise is related to the number of cakes
that reid has sold.

money left to raise

Explanation:

Step1: Determine the slope of the line

The line goes from ($300$, $100$) to ($700$, $0$). The slope $m=\frac{y_2 - y_1}{x_2 - x_1}=\frac{0 - 100}{700 - 300}=\frac{- 100}{400}=-\frac{1}{4}$. The equation of the line in point - slope form using the point ($700$, $0$) is $y-0 =-\frac{1}{4}(x - 700)$, which simplifies to $y=-\frac{1}{4}x+175$.

Step2: Find the number of cakes when $y = 500$

We want to find $x$ when $y = 500$. Substitute $y = 500$ into the equation $y=-\frac{1}{4}x + 175$. Then $500=-\frac{1}{4}x+175$.
Subtract 175 from both sides: $500 - 175=-\frac{1}{4}x$. So $325=-\frac{1}{4}x$.
Multiply both sides by - 4: $x=-4\times325=- 1300$ (This is wrong. Let's use the graph directly).
Looking at the graph, when the money left to raise ($y$ - axis) is $500$, we find the corresponding value on the $x$ - axis (cakes sold).
We can see that when the money left to raise is $500$, the number of cakes sold is $50$.

Answer:

50 cakes