Answer:
Step-by-step explanation:
The vertices lie on the x-axis, as is determined by their coordinates. This makes the center of this hyperbola (0, 0) because the center is directly between the vertices. The fact that the foci also lie on the x-axis tells us that this is the main axis. What this also tells us is which way the hyperbola "opens". This one opens to the left and the right as opposed to up and down. The standard form for this hyperbola is:
and so far we have that h = 0 and k = 0.
By definition, a is the distance between the center and the vertices. So a = 5, and a-squared is 25. So we're getting there. Now here's the tricky part.
The expressions for the foci are (h-c, k) and (h+c, k). Since we know the foci lie at +/-13, we can use that to solve for c:
If h+c = 13 and h = 0, then
0 + c = 13 and c = 13.
We need that c value to help us find b:
and
and
and
so
b = 12. Now we're ready to fill in the equation:
and there you go!
300 cookies were ordered to start.
We can tell this because we know 12% is equal to 36. Because this is true, we can set up a proportion to solve. All proportions can be set up with the small number on top and the total on the bottom. This will help you solve for the missing number, which is in this case the total number of cookies. Let x be the total number of cookies.
Percentage/total percentage = cookies/cookies total
12/100 = 36/x
Now we can cross multiply to solve.
(100)(36) = (12)(x) ----> multiply
3600 = 12x ---> divide by 12
300 = x
The first step of finding the percent tip, we must find how much tip she paid:
Tip = $38.61 - $33 = $5.61
To find the percent tip, we must divide the tip amount by the amount she paid before the tip
$5.61 / $33 = 0.17 --> 17%
Thus the percent tip is 17%
Hope that helps!
Answer:
872 is the final answer
Step-by-step explanation: