Answer:
X = 2 or X = 3
Explanation:
Substitute the given values in the given equation and solve the quadratic.
angle 1 = angle 2 + angle 3
2x^2 +6 = (x^2 +x) +(4x)
2x ^2 +6 = x^2 +5x . . . . . . . . collect terms
x^2 -5x +6 = 0 . . . . . . . . . . . subtract x^2 +5x
(x -2)(x -3) = 0 . . . . . . . . . . factor
x may be either 2 or 3.
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Additional comment
Solutions to a factored quadratic are the values of x that make the factors zero.