Question
What is the equation of the line passing through #(13,-4)# and #(14,-9)#?
Answers
#y + 4 = -5(x-13)# Explanation:
I'm not sure which form of equation you want it to be in, but going to show the simplest, or point-slope form, which is
#y - y_1 = m(x-x_1)# .First, we need to find the slope of the line,
#m# .To find the slope, we use the formula
#m = (y_2-y_1)/(x_2-x_1)# , also known as "rise over run", or change of#y# over change of#x# .Our two coordinates are
#(13, -4)# and#(14, -9)# . So let's plug those values into the slope equation and solve:
#m = (-9-(-4))/(14-13)#
#m = -5/1#
#m = -5# Now, we need a set of coordinates from the given or the graph. Let's use the point
#(13, -4)# So our equation is:
#y-(-4) = -5(x-13)# Simplified...
#y + 4 = -5(x-13)#
#y=-5x+61# 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"#
#"to calculate m use the "color(blue)"gradient formula"#
#color(red)(bar(ul(|color(white)(2/2)color(black)(m=(y_1-y_1)/(x_2-x_1))color(white)(2/2)|)))#
#"let "(x_1,y_1)=(13,-4)" and "(x_2,y_2)=(14-9)#
#rArrm=(-9-(-4))/(14-13)=-5#
#rArry=-5x+blarrcolor(blue)"is the partial equation"#
#"to find b use either of the two given points"#
#"using "(13,-4)#
#-4=-65+brArrb=61#
#rArry=-5x+61larrcolor(red)"in slope-intercept form"#