Factor to this equation out, the easiest way is to solve for the two x values that add up to -1 but when multiplied is equal to -6. It should look like this: (x +- ?)(x +- ?).
The factored out form is then (x - 3)(x +2), because -3 + 2 = -1 and when multiplied together gives -6.
x - 3 = 0
x = 3
x + 2 = 0
x = -2
The two solutions are therefore, x = 3 and x = -2.
Hope it helps
Angle pair 1 and 2 are vertical.
Angle pair 5 and 6 are adjacent.
Your question: Find D in | - 2d|<10
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SOLVING....
Solve the absolute value
|−2d| < 10
=
−2d < 10
or
−2d > −10
Solve −2d < 10 for D
Divide each side by -2
-2d ÷ -2 < 10 ÷ -2
d > -5
Now Solve −2d > −10
Divide each side by -2
-2d ÷ -2 > -10 ÷ -2
d < 5
So D is d < 5 and d > -5
The angle adjacent to angle 6 is the one we need to find first. To do this, add the measures of the intercepted arcs and divide by 2. 60 + 50 = 110, and half of that is 55. That means that both adjacent angles to the angle 6 are 55 (vertical angles are congruent). The measure of all the angles added together is 360 and angle 6 is vertical to the other "sideways" angle, so they are congruent as well. 360 - 55 - 55 = 250. Split that up between angle 6 and its vertical angle to get that each of those measure 125. Angle 6 measures 125, choice b from above.