Question

What is the y-intercept of the linear equation shown on the graph?

Answer 1

y = mx+b is the slope intercept form. b is the y intercept so to find the y intercept we have to solve the equation for b

first find the slope- represented by the variable m.
slope formula is y2-y1/x2-x1
the two points i’ve chosen to plug in are (110,5) and (120,10)
10-5/ 120-110
5/10 which reduces to 1/2

now for y and x in the slope intercept equation we can choose any point on the line and substitute the letters for the corresponding points. we’ll do (110,5)

5=(1/2)(110)+ b
5= 55+b
subtract 55 from both sides
-50=b

the y intercept is -50

Answer 2

You can see it is going up 5 and right 10. The slope would be 5/10 (or 1/2).

Since we need to go left 100 units because the x-intercept is (100,0), we will need to repeat the down 5 left 10, 10 times.

-5*10/-10*10 = -50/-100. We will go down -50 times and left -100 which would hit the y-axis. The y-intercept would be -50.

f(x) or y = 1/2x - 50

Double check your work.

y = 1/2 (100) - 50

y = 50 - 50

y = 0 √