Question 55144
y=mx+b [Slope-intercept formula of a line]
m=(y-y2)/(x-x2) [Formula for the slope of a line]
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(0,0)(4,5) [Given coordinate points of a line]
m=(5-0)/(4-0)=5/4
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y=mx+b [Plug-in the values using the slope and the values of one point]
5=(5/4)(4)+b [Solve for b]
5=5+b
5-5=b
0=b
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y=(5/4)x+0 [Plug-in the values of the slope and y-intercept into the slope-intercpet formual]
y=5/4x [Slope-intercept form of the line]
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Check by plugging the second set of coordinate points into the formula:
(0,0)
y-mx+b
0=(5/4)(0)+0
0=0 [Checks out]

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{{{ graph( 300, 200, -6, 5, -10, 10, (5/4)x) }}}