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Whats the y intercept in x + y = –3

User Mira
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2 Answers

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Answer: Slope = -2.000/2.000 = -1.000

x-intercept = -3/1 = -3.00000

y-intercept = -3/1 = -3.00000

Explanation:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

x+y-(-3)=0

STEP

1

:

Equation of a Straight Line

1.1 Solve x+y+3 = 0

Tiger recognizes that we have here an equation of a straight line. Such an equation is usually written y=mx+b ("y=mx+c" in the UK).

"y=mx+b" is the formula of a straight line drawn on Cartesian coordinate system in which "y" is the vertical axis and "x" the horizontal axis.

In this formula :

y tells us how far up the line goes

x tells us how far along

m is the Slope or Gradient i.e. how steep the line is

b is the Y-intercept i.e. where the line crosses the Y axis

The X and Y intercepts and the Slope are called the line properties. We shall now graph the line x+y+3 = 0 and calculate its properties

Graph of a Straight Line :

Calculate the Y-Intercept :

Notice that when x = 0 the value of y is -3/1 so this line "cuts" the y axis at y=-3.00000

y-intercept = -3/1 = -3.00000

Calculate the X-Intercept :

When y = 0 the value of x is -3/1 Our line therefore "cuts" the x axis at x=-3.00000

x-intercept = -3/1 = -3.00000

Calculate the Slope :

Slope is defined as the change in y divided by the change in x. We note that for x=0, the value of y is -3.000 and for x=2.000, the value of y is -5.000. So, for a change of 2.000 in x (The change in x is sometimes referred to as "RUN") we get a change of -5.000 - (-3.000) = -2.000 in y. (The change in y is sometimes referred to as "RISE" and the Slope is m = RISE / RUN)

Slope = -2.000/2.000 = -1.000

Geometric figure: Straight Line

Slope = -2.000/2.000 = -1.000

x-intercept = -3/1 = -3.00000

y-intercept = -3/1 = -3.00000

User Aadith Ramia
by
5.0k points
3 votes

Answer:

the y-intercept is -3

Explanation:

x+y=3

-x -x

y=-x-3

b=-3

User GavinR
by
4.7k points