How do you find the slope and y intercept for y + 4 = 2x?

2 Answers
Mar 11, 2016

m=2

q=-4

Explanation:

We need to transform the equation in the form:

y=mx+q

where

slope=m

and

y_(nn)=q (with y_(nn) as y intercept)

y+4=2x<=>y=2x-4

Therefore:

m=2

q=-4

graph{2x-4 [-3.862, 6.004, -4.428, 0.506]}

Mar 11, 2016

Same thing just, presented a bit differently!

color(blue)("The slope " = " " 2)
color(blue)(" " y_("intercept ")=-4)

Explanation:

Given:" "y+4=2x

You could transform this into the standard format of y = mx+c but in this case we do not have to do so to determine what we are asked to.

'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The y-intercept is when x=0 This is because the y-axis crosses the x-axis at x=0

So we write the equation as: y+4=2xx0

But 2xx0 = 0 giving

color(brown)(y+4=0)

Subtract" "color(blue)( 4 )" "from both sides

color(brown)(y+4color(blue)(-4)=color(blue)(-4))

But 4-4 = 0 giving

color(green)(y+0=-4" so " y_("intercept")=-4)
'~~~~~~~~~~~~~~~~~~~~~~~~~~~

The slope (gradient) is the number in front of x" ( the coefficient of "x) which is 2

color(green)("The slope "=2)
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~