Respuesta :

Answer:

the answer is x=15 cm

Step-by-step explanation:

here the above given figure is a rectangle ABCD with diagonals AC and BD measuring AC= (x+10)cm and BD=(3x-20) cm

Now,

AC=BD

or, 3x-20 = x+10 [ diagonals of a rectangle are equal]

or, 2x = 30

or, x= 15 cm

I HOPE IT WILL HELP YOU!!!