find the equation of the line through the points (6,7) (2, -1)

Question

campbell_st · Answer

find the gradient 1st rise/run or$$m =(y _{2} -y _{1})/(x _{2} - x _{1})$$

so ( -1 - 7)/(2-6) = -8/-4  =2

the gradient is m = 2

use the point gradient formula with either point... 

$$y - y _{1}=m(x - x _{1})$$

anonymous · Answer

that what i did but have have to get it equal to y which im having trouble doing...

anonymous · Answer

i have y-7=2 (x+6) so far...

campbell_st · Answer

add 7 to both sides... 

and expand the brackets

anonymous · Answer

sooo y=2(x+6+7) ? i put in y=2(x+13) and it was wrong.

campbell_st · Answer

y = 2(x+6) +7

anonymous · Answer

that is still coming up as wrong :(

anonymous · Answer

$$y=mx+b $$ Use your two points (ordered pairs) to find the slope (rise over run or the difference of the Ys over the differences over the Xs).  $$(-1-7)/(2-6)$$  You can simplify this to 2.  This gives you...$$y=2x+b$$.  B is your Y-intercept (where the line crosses the Y-axis, or when X is zero).   To solve for B with a known point and slope, fillin all the known variables and solve for B.$$-1=2*2+b$$$$-1=4+b$$$$b=-5$$  Now you have the your Y-intercept.  Your equation should look like this.$$y=2x-5$$