The product (x) of two numbers is 24 and their sum (+) is 10. What is the value of the largest of the two numbers?
1 answer:
let the two numbers be x and y
From the first sentence,
xy=24
x+y=10
Then make y in equation 2 the subject of the formular and substitute in equation 1
x+y=10
y=10-x
substituting in equation 2
x(10-x)=24
open the bracket
10x-x^2=24
=-x^2+10x=24
Transfer the constant to the left hand side
=-x^2+10x-24=0
Then factorise completely
Look at the photo above
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The slope is a measure of how high or low the line is. The number is a ratio between the rise and run of a slope. In other words, it is essentially
Let's look back at the graph. In the time interval from 1 to 2 seconds, we see that the line rises by 22 feet. Because the time interval is only 1 second, the run is 1 second.
Therefore:
m =
m =
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We now have the first variable of the equation.
y = 22x + b
What about b? As we established earlier, b is the value of coordinate y at the y-intercept. Essentially, to find b we need to know what the value of y is when the coordinate x is 0.
As you can see from the graph you made, the value of y when x is 0 is also 0. This makes sense, too. How can the cheetah travel distance at 0 seconds when it obviously hasn't started moving? We now know b = 0. Now, we have gotten all of the variables we need to make a full equation:
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If you'd like me to explain how I did anything, just ask!
- breezyツ