SOLUTION: I need to find the x intercept of this equation. I just dont get any of it. 4x+5y=8

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Question 389461: I need to find the x intercept of this equation. I just dont get any of it.
4x+5y=8
Found 4 solutions by Fombitz, ewatrrr, MathLover1, Earlsdon:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Set x=0 and solve for y.
.
.
4x%2B5y=8
4%280%29%2B5y=8
0%2B5y=8
5y=8
highlight%28y=8%2F5%29
So the y-intercept is (0,8%2F5).

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,         

 4x + 5y = 8  This type of equation always represents a line graphically.

Cartesian plane has an x and y axis.  x axis labeled on graph

Question being asked is where does this line cross the x-axis:

The line will cross the x axis when y  = 0

4x + 5y = 8  when y = 0

4x + 5*0 = 8

 4x = 8

  x = 2

x-intercept is Pt(2,0) (When naming points, the x value is placed first)

Pt(1,4/5) and Pt(3,-4/5) are a couple more points on the line.

these found by substituting x value into the equation.

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

remember:
an x-intercept is a point on the graph where y is zero
a y-intercept is a point on the graph where x is zero

4x%2B5y=8....so, to find the x-intercept of this equation, set y to 0
4x%2B5%2A0=8
4x=8
x=8%2F4
x=2....so, the x intercept of this equation is (2,0)

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
It sounds like you're having a tough time with algebra, huh?
Let's see if I can explain how to do this problem.
Find the x-intercept of:
4x%2B5y+=+8
When you graph this "linear" equation (I'll do that in a bit), you get a straight line. This is why we call this a "linear" equation.
Now this straight line may cross or intercept the x-axis (of course, it may also intercept the y-axis).
You are being asked to find the value of the x-coordinate of the point on the x-axis where this line crosses it.
There are a couple of ways to do this.
Graph the equation and inspect the graph for the crossing point. Let's do that now.
First we need to get this equation into the "slope-intercept" form: y+=+mx%2Bb where m is the slope of the line and b is the y-intercept.
4x%2B5y+=+8 We need to get the y all by itself on the left side so first subtract 4x from both sides of the equation.
4x-4x%2B5y+=+-4x%2B8
5y+=+-4x%2B8 Now divide both sides by 5 to isolate the y.
5y%2F5+=+%28-4%2F5%29x%2B8%2F5 Simplify.
highlight%28y+=+%28-4%2F5%29x%2B8%2F5%29 Now we can graph this equation:
graph%28400%2C400%2C-5%2C5%2C-5%2C5%2C%28-4%2F5%29x%2B8%2F5%29
Now you can see from the graph that the line intersects the x-axis at highlight%28x+=+2%29 so this is the x-intercept for this equation.
The other way to find the x-intercept is to do it algebraically.
You'll notice on the graph that x-axis crosses the y-axis at y = 0, so if we set y = 0 in the given equation and solve for x, we will have the x-intercept.
Start with the given equation:
4x%2B5y+=+8 Substitute y=0.
4x%2B5%280%29+=+8 simplify.
4x+=+8 Now divide both sides by 4.
4x%2F4+=+8%2F4 Simplify.
highlight%28x+=+2%29
I hope this helps!