How do you find the general form of the line passing through (-1,2) and (2,5)?

2 Answers
Jun 11, 2017

y=x+3

Explanation:

First, find the slope. To do this, plug in values for this equation.
#m=(y2-y1)/(x2-x1)#
m is the slope and the values are your original coords.
#m=(5-2)/(2--1)#
#m=3/3#
#m=1#
Now that we have the slope, we use it to find the y-intercept, and the slope-intercept form.
We use point-slope for this.
#y-y1=m(x-x1)#
#y-2=1(x--1)#
#y-2=(x+1)#
#y-2=x+1#
#y=x+3#
The slope is 1, and the y-intercept is 3. The slope-intercept form is "y=x+3", and the point-slope form is "y-2=1(x+1)"

Jun 11, 2017

#x-y+3=0#

Explanation:

#"the equation of a line in "color(blue)"general form"# is.

#color(red)(bar(ul(|color(white)(2/2)color(black)(Ax+By+C=0)color(white)(2/2)|)))#
where A is a positive integer and B, C are integers.

#"to begin express the equation in "color(blue)"slope-intercept form"#

#• y=mx+b#

#"where m represents the slope and b, the y-intercept"#

#"to calculate m use the "color(blue)"gradient formula"#

#color(red)(bar(ul(|color(white)(2/2)color(black)(m=(y_2-y_1)/(x_2-x_1))color(white)(2/2)|)))#
where # (x_1,y_1),(x_2,y_2)" are 2 coordinate points"#

#"the points are " (x_1,y_1)=(-1,2),(x_2,y_2)=(2,5)#

#rArrm=(5-2)/(2-(-1))=3/3=1#

#rArry=x+blarr" is the partial equation"#

#"to find b use either of the 2 given points"#

#"using " (2,5)" then"#

#5=2+brArrb=3#

#rArry=x+3larrcolor(red)" in slope-intercept form"#

#rArrx-y+3=0larrcolor(red)" in general form"#