SOLUTION: write an equation in slope-intercept form for the line that satisfies the following condition. slope 1/3and passes through (3,9)

Algebra ->  Linear-equations -> SOLUTION: write an equation in slope-intercept form for the line that satisfies the following condition. slope 1/3and passes through (3,9)      Log On


   



Question 157640This question is from textbook algebra 2
: write an equation in slope-intercept form for the line that satisfies the following condition. slope 1/3and passes through (3,9) This question is from textbook algebra 2

Answer by Electrified_Levi(103) About Me  (Show Source):
You can put this solution on YOUR website!
Hi, Hope I can help
.
write an equation in slope-intercept form for the line that satisfies the following condition. slope +1%2F3+ and passes through (3,9)
.
The slope intercept form of an equation is equal to +y+=+mx+%2B+b+, where "m" is the slope, "b" is the y intercept.
.
We know the slope is +1%2F3+, so we can replace "m" with +1%2F3+ in our equation
.
+y+=+mx+%2B+b+, becomes +y+=+%281%2F3%29x+%2B+b+, now we have to find "b"
.
We now a point on the line, point (3,9), and because points are given as (x,y), we can use the point to solve for "b"
.
If the point is (3,9)(x,y), all we need to do is replace "x" and "y" in our equation, with the numbers(replace "x" with "3", replace "y" with "9")
.
+y+=+%281%2F3%29x+%2B+b+, becomes +%289%29+=+%281%2F3%29%283%29+%2B+b+
.
+%289%29+=+%281%2F3%29%283%29+%2B+b+ = +%289%29+=+%281%29+%2B+b+
.
+%289%29+=+%281%29+%2B+b+ = +9+=+1+%2B+b+, to find "b" we will move "1" to the left side
.
+9+=+1+%2B+b+ = +9+-+1+=+1+-+1+%2B+b+
.
+9+-+1+=+1+-+1+%2B+b+ = +8+=+b+ = +b+=+8+
.
We found that "b" = "8", we can replace "b" with "8" in our equation
.
+y+=+%281%2F3%29x+%2B+b+ = +y+=+%281%2F3%29x+%2B+8+
.
+y+=+%281%2F3%29x+%2B+8+ is the slope-intercept form/equation of the line
.
We can check our answer by replacing "x" and "y" with (3,9)(x,y) in our equation
.
+y+=+%281%2F3%29x+%2B+8+ = +%289%29+=+%281%2F3%29%283%29+%2B+8+
.
+%289%29+=+%281%2F3%29%283%29+%2B+8+ = +%289%29+=+%281%29+%2B+8+
.
+%289%29+=+%281%29+%2B+8+ = +9+=+1+%2B+8+ = +9+=+9+ (True)
.
We can also find that the y intercept(where the line hits the y-axis) is (0,8), another point on the line,
.
We can check by replacing "x" and "y" with (0,8)(x,y),
.
+y+=+%281%2F3%29x+%2B+8+ = +%288%29+=+%281%2F3%29%280%29+%2B+8+
.
+%288%29+=+%281%2F3%29%280%29+%2B+8+ = +%288%29+=+%280%29+%2B+8+
.
+%288%29+=+%280%29+%2B+8+ = +8+=+0+%2B+8+ = +8+=+8+ (True)
.
The slope-intercept form/equation of the line is +y+=+%281%2F3%29x+%2B+8+
.
Hope I helped, Levi