Answer:
y = 3/8x
or
3/8 cups of sugar for every 1/2 batch of muffins
Step-by-step explanation:
Since we are only making 1/2 of the full batch of muffins, we only need to use 1/2 the cups of sugar:
cups of sugar.
We have to write an equation that uses this info so we can find the cost to ship that package. However, the package weight is given to us in grams and we need it in ounces. So first thing we are going to do is convert that 224 g to ounces. Use the fact that 1 g = .035274 ounces to convert. 
. Do the multiplication and cancel out the label of grams and we have 7.901376 ounces. Ok. We know that it costs .57 to mail the package for the first ounce. We have almost 8 ounces. So no matter what, we are paying .57. For each additional ounce we are paying .32. The number of .32's we have to spend depends upon how much the package goes over the first ounce. For the first ounce we pay .57, then for the remaining 6.901376 ounces we pay .32 per ounce. Our equation looks like this: C(x) = .32(6.901376) + .57 and we need to solve for the cost, C(x). Doing the multiplication we find that it would cost $2.78 to ship that package.
Slope-intercept form is y = mx +b, where the variable m represents the slope of the line and the variable b represents the y-intercept of the line. Since we weren't given the y-intercept, one way to solve this problem is substitute the slope for the variable m and then the x and y values from the ordered pair to solve for b.
y = mx + b
y = 3x + b
-4 = 3(9) + b
Now, we can simplify by computing the multiplication on the right side of the equation.
-4 = 27 + b
Finally, we can find the value for b by subtracting 27 from both sides of the equation to get:
-31 = b
Now, we should substitute this value for b back into our equation with the slope.
y = 3x - 31
Therefore, your answer is y = 3x - 31.
Hope this helps!
