How do you find the x and y intercept of 3x − y = 5 ?

1 Answer
Jul 7, 2016

x_("intercept")=5/3

y_("intercept")=-5

Explanation:

color(blue)("Determine "y_("intercept"))

The y-axis crosses the x-axis at x=0 so to find the y-intercept substitute x=0 into the equation

color(brown)(3x-y=5)color(blue)(" "->" "3(0)-y=5

But 3xx0=0 giving

-y=5

Multiply both sides by (-1)

(-y)xx(-1)=5xx(-1)

y=-5
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color(blue)("Determine "x_("intercept"))

The x-axis crosses the y-axis at y=0 so to find the x-intercept substitute y=0 into the equation

color(brown)(3x-y=5)color(blue)(" "->" "3x-0=5

color(brown)(3x=5)

Divide both sides by color(blue)(3)

color(brown)(3/(color(blue)(3)) xx x=5/(color(blue)(3))

But 3/3=1

x=5/3

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(brown)(3x-y=5)" "->" "color(blue)(y=3x-5)
Tony B