How do you find the equation of a line when given?

Question

either the y-intercept and one point or the x-intercept and one point?

Answer 1

you 1st find the gradient using the formula (y2 - y1)/(x2 - x1), using your points (x1, y1) and (x2, y2).

you then use y = mx + c using either of your two points for the y and the x as long as they both come from the same point. i.e. not x1 and y2.

solve for c and then the equation is y=mx + c where you know m and c.

Answer 2

If you have the y intercept and one point, then you actually have -2- points, so you use the same equation(s) you'd use if you just had 2 points, since the y intercept is at (0,y).

Same for the x intercept. It's at (x, 0)

Doug

Answer 3

Use the y-intercept coordinate (0,y) and your other point to find the slope of your line. Slope formula for points (x1,y1) and(x2,y2)=
(y2-y1)/(x2-x1)
Then use the equation y=mx+b (m=slope, b=y-intercept). Plug in the slope and the y-intercept and you'll get your equation of a line.

Use the x-intercept coordinate (x,0) and your other point to find the slope of your line.
Then use the same equation, y=mx+b, to plug in your slope and the given point. Then solve for b. Plug in your b value and the slope, and you have an equation for a line.

Answer 4

you can always frame the equation
from (y-k) = m(x - h)
where h, k are x and y coordinates of the given point.
when y intercept is given, the coordinates of the other point are (0,b)where b = y intercept.
when x intercept is given, the coordinates are(a, 0), where a is the x intercept.
so slope, m = (k- b)/(h -0) when y intercept is known
(k -0)/(h - a) when x intercept is known

Answer 5

y=mx+b

you just take the numbers and plug it in.
If you were given Y intercept of 4, and point (4,8)
You plug in everything so the equation would read:
8=4x+4
so
4=4x
x=1

Just plug in the X if you have the x intercept and a point,

Hope this helps!

Answer 6

you find the slope using the y intercept and the one point and once you find the slope and then u use the pt slope formula to get the equation

Answer 7

try x = 0 and find the result for y

y = 0 and find the result for x

plot these and join them to get your line (assuming it follows a y = mx + c format)

Answer 8

suppose you got (0,y_1) and another point P(x_2,y_2)
Then the equation of the line is
y-y_2 = m (x-0)
where m = (y_2-y_1)/(x_2-0)