Lois C. answered 04/13/20
BA in secondary math ed with 20+ years of classroom experience
Assuming that point E is the point of intersection of the two diagonals of the rhombus, we will begin with the area formula for a rhombus which is A = 1/2( d1 x d2 ), where d1 and d2 are the two diagonals of the rhombus. Since we are already given the area and the length of one diagonal, we insert those values into the formula:
350 = 1/2 (28)( AC). Solving for AC, we find that AC = 25. Since the two diagonals in any rhombus bisect each other, we divide AC by 2 to find that AE = 12.5, so x = 12.5 cm.