Question

∠A and \angle B∠B are vertical angles. If m\angle A=(3x-30)^{\circ}∠A=(3x−30)

Answer 1

Answer:

$x=21\textdegree$

Step-by-step explanation:

So we know that:

$\angle A=3x-30 \text{ and}\\\angle B=2x-9$

And that the two angles are vertical angles.

Since they are vertical angles, their measurements are equivalent. Thus, to find x, set the equations equal to each other:

$\angle A=\angle B\\(3x-30)=(2x-9)$

Now, solve for x. Add 30 to both sides. The left side cancels:

$(3x-30)+30=(2x-9)+30\\3x=2x+21$

Now, subtract 2x from both sides. The right cancels:

$(3x)-2x=(2x+21)-2x\\x=21$

Thus, the value of x is 21.