First of all we need the line equation so let's find it first :
y = mx + b
y = 2x + b
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The line passes through point ( 8 , 3 ) which means if put 8 instead of x the y must equals to 3 :
2(8) + b = 3
16 + b = 3
b = 3 - 16
b = - 13
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Now we have the equation of the line :
y = 2x - 13
To find the y-intercept we just need to out 0 (zero ) instead of x ; Let's do it :
y = 2(0) - 13
y = 0 - 13
y = - 13
Thus the y-intercept = - 13
