First off, if they’re vertical angles, they have to be congruent. So set the equation up as x=4x-30. Then solve and get the answer of x=10. Therefore your angle measure is 10 degrees
Since
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we know our function is
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.
To solve, substitute the given value:
All of the angles would be acute angles because they are less then 90 degrees
Subtract 4 from both sides. You'll get 8x = 28. Solving for x, x = 28/8 = 7/2