There is a book sale at the library. The price for each book is $4. Which expression can be used to show how much money the libr
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Answer:
x-int = 18
y-int = -9/2
Step-by-step explanation:
Use slope-intercept form y=mx + b
To find the slope, substitute the two points into the slope formula and solve.
Substitute a random point (2,-4) and m=1/4 into slope-intercept form
y = mx+b
-4 = 1/4 (2) + b
-4 = 2/4 + b
-4 = 1/2 + b
Isolate b to solve
b = -4 - 1/2
b = -8/2 - 1/2
b = -9/2 <= this is the y-intercept
b is the y-intercept in slope-intercept form
Substitute b= -9/2 and m=1/4 to get the equation of the line.
y = 1/4 x - 9/2
Substitute y for 0 to find the x intercept
y = 1/4 x - 9/2
0 = 1/4 x - 9/2
9/2 = 1/4 x
x = (9/2) / (1/4)
x = (9/2) X (4/1)
x = 36/2
x = 18