The equation for the line
is:
y-y1 = m (x-x1)
We have
the point (3,4) psses through the line,
==> y-4 =
m(x-3)
==> y = mx - 3m +
4
==> y - mx = -3m +
4
Divide by -3m +
4:
==> y/(-3m+4) + x/[(-3m+4)/-m] =
1
==> y intercept a =
-3m+4
==> x intercept b =
(-3m+4)/-m
But we know that a+ b =
14
==> -3m + 4 + (-3m+4)/-m =
14
==> -3m + 4 + 3 - 4/m =
14
==> -3m^2 + 7m - 4 =
14m
==> -3m^2 - 7m - 4 =
0
==> m1= [7+ sqrt(49-48)]/-6 = [7+1]/-6 = -8/6=
-4/3
==> m2= [7-1]/-6= 6/-6 =
-1
==> we have two
solutions:
m= -4/3:
==>
y-4 = (-4/3)(x-3)
==> y= (-4/3)x +
8
m= -1:
==> y-4 =
(-1)(x-3)
==> y= -x +7
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