Step-by-step explanation:
As it is said that the triangles are similar so the ratio of the corresponding sides are equal so
AB / ED = BC / EF
x² / 18 = 7 / 14
x² / 18 = 1 / 2
2x² = 18
x² = 18 / 2
x² = 9
x² =( + 3)²
Therefore
x = 3 or x = - 3
Hope it will help :)❤
