Question

How do you find X and Y intercepts

Answer 1

X and Y intercepts are when a function crosses the x or y axis.
x-intercepts are at (x-value, 0) and y-intercepts are at (0, y-value).

To find the place where a function crosses the x or y axis, you must plug zero in for the opposit variable. This means plugging in 0 in the equation for y when you try to find x-intercepts and 0 in for x when you try to find y-intercepts, and then solve.

EX. the simple linear equation y = 4x + 2

find the x-intercept: 0 = 4x +2
-2 -2
------------
4
(-.5, 0)

find the y-intercept: y = 4(0) +2
y= 2
(0,2)

Answer 2

the x intercept is when the line crosses the x axis
the place where the line crosses the x axis is also when y=0
the y intercept is when the line crosses the y axis
the place where the line crosses the y axis is also when x=0

so lets say you have the equation in slope-intercept form
which is y=mx+b

m=slope
b=y-intercept

to find the x intercept, set y to zero and solve
to find the y intercept, find b or set x to zero and solve (which cancels out mx and leaves b)

so exg
y=3x+4
x intercept=y=0 so 0=3x+4
subtract 4 from both sides
-4=3x
divide boht sides by 3
-4/3=x intercept


so y intercept
y=3(0)+4
y=0+4
y=4=y intercept