12th is a parallelog rat 7 a 30 SolutionSince ABCD is a para

Solution

Since ABCD is a parallelogram opposite sides are equal

Therefore X = 8 ft

Also, Y is a diagonal of parallelogram

Formula of parallelogram diagonal in terms of two sides and other diagonal:
d₁ = 2a² + 2b² - d₂²

Or We can consider the triangle ACD and use the law of cosines

c² = a² + b² - 2abcos(C)

Here C = 88^o which is <D

AC² = AD² + DC² - 2AB.BA cos(<D)