Try to solve for x, i cant figure it out

Answer:
Step-by-step explanation:
From the upper isosceles triangle,
The answer is: x=±√5y [Note: If and only if at the lower triangle is NOT isosceles]
Exterior angle to the isosceles triangle = 2(2x^2 – 2x) [because the exterior angle of a triangle is equal to the sum of two opposite interior angles]
Therefore, the exterior angle = 4x^2 – 4x
Also,
The exterior angle is equal to the sum of the two interior base angles of the lower triangle
Thus, 4x^2 – 4x=(3x^2+4x) + (5y – 8x)
By collecting like terms,
4x^2 – 3x^2 – 4x – 4x + 8x – 5y = 0
x^2 – 5y = 0
x^2 = 5y
By taking the square root of both sides
x=±√5y
Learn more about triangles at brainly.com/brainly.com/question/29069807
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