Question

What is the slope-intercept form of the equation of the line with a slope of 1/4 and y-intercept at the origin?

Answer 1

m = 4. Also, in giving me a point on the line, they have given me an x-value and a y-value for this line: x = –1 and y = –6.

solve for b:

y = mx + b

(–6) = (4)(–1) + b

–6 = –4 + b

–2 = b

Then the line equation must be y= 4x – 2

m=

(−2)−(1)

(4)−(2)

= −3/2

=− 3/2

Using the point (–2, 4), I get:

y = mx + b

4 = (– 2/3)(–2) + b

4 = 4/3 + b

4 – 4/3 = b

12/3 – 4/3 = b

b = 8/3

...so y = ( – 2/3 ) x +

On the other hand, if I use the point (1, 2), I get:

y = mx + by=mx+b

2 = - + b2=−

3

2

(1)+b

2 = - {2}{3} + b2=− 3/2

+b

{2}{3} = b 3/6

+

3

2

=b

{8}{3} = b 3/8

=b

So it doesn't matter which point I choose. Either way, the answer is the same:

y=− 3/2×x+ 3/8

Answer 2

Answer:

y=1/4x+0

(y=mx+b)