# What is the slope and y-intercept of : 4x-5y=20

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The equation of a line can be expressed as y = mx + b where m is the slope and b is the y intercept. To find the slope and y-intercept of 4x - 5y = 20 write the equation in the format y = mx + b

4x - 5y = 20

=> 5y = 4x - 20

=> y = (4/5)x - 4

**The slope of the line representing the equation 4x - 5y = 20 is (4/5) and the y-intercept is -4.**

4x-5y=20

4x-5y-4x=20-4x

-5y=20-4x

-5y/-5=20/-5-4x/-5

y=-4+0.8x

y=0.8x-4

slope=0.8

y-intercept=-4

You must get the equation into the y=mx + b, where m is the slope and b is the y-intercept.

4x - 5y = 20

4x - 5y + 5y = 20 + 5y

4x = 20 + 5y

4x - 20 = 20 + 5y - 20

4x - 20 = 5y

(4x - 20)/5 = 5y/5

4/5x - 4 = y

y = 4/5x - 4

So m, or slope, is 4/5

b, or y-intercept, is -4, or (0, -4)

You solve the equation for y. The number in front of x is the slope and the integer is y-intercept Y= 4/5x - 4. To graph it you graph the y intercept (-4) by going to -4 on y axiis and from -4 you go up 4 and over 5. Slope equals rise over run. You draw the line though the two points. (0, -4) and (5,0)