Answer:
y+1=3(x-4)
Step-by-step explanation:
Hi there!
We are given a slope of 3 and a point (4,-1).
We need to find the equation of the line in point-slope form
Point-slope form is given as y-y1=m(x-x1), where m is the slope, and (x1,y1) is a point
We have all of the needed information to substitute into the formula
First, let's label the values of everything to avoid any confusion
m=3
x1=4
y1=-1
now substitute into the formula *remember, the formula has SUBTRACTION, and we have a NEGATIVE number, so we'll end up subtracting a negative*
y--1=3(x-4)
simplify
y+1=3(x-4)
That's it!
Hope this helps :)
Answer:
y = 10/9x + 9
Step-by-step explanation:
To write the equation in its slope-intercept form, y = mx + b, we need to find the slope (m) of the line and its y-intercept (b).
Given the points (0, 9) and (9, 19), we can solve for the slope of the line using the following formula:
![m = \frac{y2 - y1}{x2 - x1}](https://tex.z-dn.net/?f=m%20%3D%20%5Cfrac%7By2%20-%20y1%7D%7Bx2%20-%20x1%7D)
Let (x1, y1) = (0, 9)
and (x2, y2) = (9, 19)
Substitute these values on the formula:
![m = \frac{y2 - y1}{x2 - x1} = \frac{19 - 9}{9 - 0} = \frac{10}{9}](https://tex.z-dn.net/?f=m%20%3D%20%5Cfrac%7By2%20-%20y1%7D%7Bx2%20-%20x1%7D%20%3D%20%5Cfrac%7B19%20-%209%7D%7B9%20-%200%7D%20%3D%20%5Cfrac%7B10%7D%7B9%7D)
Therefore, the slope (<em>m </em>) = 10/9.
Next, the <u>y-intercept</u> is the point on the graph where it crosses the y-axis, and has the coordinates, (0, <em>b </em>). It is also the value of the y when x = 0.
One of the given points is the y-intercept of the line, given by (0, 9). The y-coordinate, 9, is the value of b.
Therefore, the linear equation in slope-intercept form is: y = 10/9x + 9
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Question
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![\boxed { \frac{n+h}{5} = \frac{f+9}{9}}](https://tex.z-dn.net/?f=%20%5Cboxed%20%7B%20%5Cfrac%7Bn%2Bh%7D%7B5%7D%20%20%3D%20%20%5Cfrac%7Bf%2B9%7D%7B9%7D%7D%20)
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Split the fraction on the left
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![\boxed { \frac{n}{5} + \frac{h}{5} = \frac{f + 9}{9}}](https://tex.z-dn.net/?f=%5Cboxed%20%7B%20%5Cfrac%7Bn%7D%7B5%7D%20%2B%20%5Cfrac%7Bh%7D%7B5%7D%20%20%3D%20%5Cfrac%7Bf%20%2B%209%7D%7B9%7D%7D%20)
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Take away h/5 from both sides
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![\boxed { \frac{n}{5} = \frac{f+9}{9} - \frac{h}{5}}](https://tex.z-dn.net/?f=%5Cboxed%20%7B%20%5Cfrac%7Bn%7D%7B5%7D%20%20%3D%20%5Cfrac%7Bf%2B9%7D%7B9%7D%20-%20%5Cfrac%7Bh%7D%7B5%7D%7D)
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Change the denominator to be the same
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![\boxed { \frac{n}{5} = \frac{5f+45}{45} - \frac{9h}{45}}](https://tex.z-dn.net/?f=%5Cboxed%20%7B%20%5Cfrac%7Bn%7D%7B5%7D%20%3D%20%5Cfrac%7B5f%2B45%7D%7B45%7D%20-%20%5Cfrac%7B9h%7D%7B45%7D%7D%20)
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Put it into single fraction
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![\boxed { \frac{n}{5} = \frac{5f+45-9h}{45} }](https://tex.z-dn.net/?f=%5Cboxed%20%7B%20%5Cfrac%7Bn%7D%7B5%7D%20%3D%20%5Cfrac%7B5f%2B45-9h%7D%7B45%7D%20%7D)
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Rearrange (This step may not be necessary)
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![\boxed {\frac{n}{5} = \frac{5f-9h+ 45}{45} }](https://tex.z-dn.net/?f=%20%5Cboxed%20%7B%5Cfrac%7Bn%7D%7B5%7D%20%3D%20%5Cfrac%7B5f-9h%2B%2045%7D%7B45%7D%20%7D)
For this case what you must do is the following rule of three:
50 ---> 100
80 ----> x
We clear x:
x = (80/50) * (100)
x = 160%
160-100 = 60%
Answer:
toni added 60% of the original value for his sale price