Question

College Algebra: Functions and Graphs: Find x- and y-intercepts: -1/2x+y-4=0
Stuck on finding y-intercept,
I KNOW HOW TO SOLVE, I MUST OF JUST MADE A SIMPLE MISTAKE...
My work so far:
AX+BY+C=0
X-int; y=0
-1/2X+0-4=0
-1/2x=4
x=-2, x-int: (-2,0)
*** y-int; x=0
-1/2(0)+y-4=0
0+y-4=0
y=4; y-int: (0,4) <--- answer key says its (-8,0) though... how??

Answer 1

-1/2x + y - 4 = 0

the y intercepts is a point on the y axis (also called the x=0 axis) so let x=0

y - 4 = 0, and y=4

your process was fine, just make sure you are matching the correct problem in the answer key maybe?

Answer 2

@amistre64 so was my answer for the y-int correct? (0,4)?

Answer 3

given: -1/2 x+y-4=0
^^ x not a denominator im assuming

then yes, the y intercept is the point (x=0, y=4)

Answer 4

given: -1/2 x+y-4=0

the x intercecpt is the point (x=-8,y=0)

Answer 5

yes not a denominator okay thank you!! :)

Answer 6

youre welcome

Answer 7

@amistre64 I keep getting (-2,0) for the x-int though.
my work:
-1/2x+y-4=0
-1/2x+0-4=0
-1/2x-4=0
-1/2x=4
-1/2x-/1/2=4/-1/2
x=-2

Answer 8

does --2/2 = 4?

Answer 9

-1/2x=4, multiply by -2

--2/2 x=4(-2)

x = 4(-2)

Answer 10

i think you were mentally messing yourself up with that.

you knew -2 was a part of the process and just skipped the final step

Answer 11

or you forgot how to divide by a fraction

Answer 12

4
---- = 4(-2/1)
-1/2

Answer 13

yep def forgot to divide by a fraction... I see it now. thank you so much for making it clear to me!

Answer 14

good luck :)

Answer 15

Thanks a billion!!!!