Search 72,229 tutors
FIND TUTORS
Ask a question
0 0

y intercept of line

Tutors, please sign in to answer this question.

2 Answers

The slope of the line will be
(1+4)/(-2+10) = 5/8
The slope intersect form will be
Y=(5/8)x + b
plugging any one of the two points we have
1=(5/8)(-2) + b
b=1+(5/4)
b= 9/4
Check
-4=(5/8)(-10) +(9/4)
-4 = -4
Check!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
First, you need to find the equation of the line. 
The form of the equation of a line given two points is the following:
 
(y-y1)/x-x1) = (y2-y1)/(x2-x1)  Let x1 = -10, y1 = -4, x2 = -2, and y2 = 1.
 
Substituting into the equation:
y-(-4) =   1-(-4)   
x-(-10)  -2-(-10)
 
 y+4     = 5     Cross multiply:
x+10       8
 
8y + 32 = 5x + 50   Solve for y:
 
8y = 5x + 18
 
y = 5 x + 18
      8        8
 
y = 5 x + 9   Since this equation is now in slope-intercept form, y = mx + b, the y=intercept is 9/4 or 2 1/4.
      8       4
 
 

Woodbridge Equations tutors