Question

Find the x-intercept and the y-intercept for the graph of the equation.
x+3y=-9

a.

–10; –2

c.

–9; –4
b.

–9; –3

d.

–8; –3

Answer 1

the first thing you would do is to get the y on one side, then the next step is to divide the -9 with the 3 to get the x intercept.

Answer 2

there is an easier way

Answer 3

x + 3y = -9
To find x intercept, sub in 0 for y and solve for x.
To find y intercept, sub in 0 for x and solve for y.

Answer 4

i really do not understand

Answer 5

I will do one...
x intercept (sub in 0 for y)
x + 3(0) = -9
x + 0 = -9
x = -9 ....so the x intercept is (-9,0)
can you find the y intercept by subbing in 0 for x ??

Answer 6

Understand ?

Answer 7

the way your answer choices are worded, the x intercept is -9

to find y intercept, sub in 0 for x
x + 3y = -9
0 + 3y = -9
3y = -9 -- divide both sides by 3
y = -9/3
y = -3
y intercept is -3

so your solution is (-9.-3)

Answer 8

any questions ?

Answer 9

No, i understand but thank you.

Answer 10

sure thing :)

Answer 11

wait i need help on another

Answer 12

3x+y=-3

Answer 13

a.

0; –3

c.

–1; –4
b.

–1; –3

d.

–2; –2

Answer 14

3x + y = 3
find the x intercept by subbing in 0 for y and solving for x.
Try it

Answer 15

oops...3x + y = -3

Answer 16

you can do this

Answer 17

let me start you off...
Looking for x intercept..sub in 0 for y
3x + 0 = -3
can you finish ?

Answer 18

do i divide next ?

Answer 19

3x = -3 --- divide both sides by 3

Answer 20

so it would be -1;-3?

Answer 21

3x/3 = -3/3 ---(the 3's on the left side cancel out)
x = -1 (-3/3 = -1)
x intercept is -1

3x + y = -3
y intercept, sub in 0 for x
3(0) + y = -3
y = -3

yes....solution is (-1,-3)

Answer 22

thank you for all your help (:

Answer 23

even if your equation is in slope intercept form, y = mx + b, you can still find the intercepts the same way.

Answer 24

what is a slope?

Answer 25

http://www.basic-mathematics.com/what-is-slope.html
ok......to find the slope, you need to put the equation in y = mx + b form, and the slope is in the m position.
For example,
2x + 4y = 9 -- subtract 2x from both sides
4y = -2x + 9 -- divide both sides by 4
y = -2/4x + 9/4 -- reduce anything that reduces
y = -1/2x + 9/4
The number in the m position is the slope. Therefore, the slope of this equation is -1/2