How do you write an equation of a line given point (3,7) and slope 2/7?

2 Answers
Apr 30, 2018

#y=2/7x+43/7#

Explanation:

#"the equation of a line in "color(blue)"slope-intercept form"# is.

#•color(white)(x)y=mx+b#

#"where m is the slope and b the y-intercept"#

#"here "m=2/7#

#rArry=2/7x+blarrcolor(blue)"is the partial equation"#

#"to find b substitute "(3,7)" into the partial equation"#

#7=6/7+brArrb=49/7-6/7=43/7#

#rArry=2/7x+43/7larrcolor(red)"equation of line"#

Apr 30, 2018

#y = (2x)/7 + 43/7# (form: y = mx + c)

#2x - 7y + 43 = 0# (form: ax + by + c = 0)

Either are acceptable answers. Your teacher may prefer a certain form.

Explanation:

By the Point-Slope Form, (which, by the way, is a method of computing the equation of a line given its slope and a point on it):

#(y - y_1) = m(x - x_1)# where #m# is the slope and #(x_1, y_1)# is the coordinates of the given point.
#(y - 7) = 2/7 (x- 3)#
#(y - 7) = (2x)/7 - 6/7#
# y = (2x)/7 +43/7#