7-4x=2-9x the answer is x=1
If

, then angle

is obtuse and triangle with sides a, b, c is obtuse triangle.
In an arbitrary triangle can be only one obtuse angle, and the side which lies opposite to the largest angle is the largest. Then since <span>angle

is opposite the side of length a</span> you can conclude that a>c and a>b.
Let x be the distance (in feet) along the road that the car has traveled and h be the distance (in feet) between the car
and the observer.
(a) Before the car passes the observer, we have dh/dt < 0; after it passes, we have dh/dt > 0. So at the instant it passes the observer we have
dh/dt = 0, given that dh/dt varies continuously since the car travels at a constant velocity.
Alternate exterior angles(AEA).
Given their relationship the angles are congruent.
8x-71=5x+7
3x-71=7
3x=78
X=26