Por qué la triangulación con dos diagonales en un rectángulo no es adecuada para calcular el área del rectángulo y calcular la suma de los ángulos internos del rectángulo

Atriangle has a side lengths of 18cm, 80 cm and 81cm. classify it as acute obtuse or right?

Afarmer has a large field that is x feet in length. he wants to fence in a rectangular section in the middle of the field , leaving a length of 100 feet of open field behind each end of the fenced rectangle. he also wants the width of the fenced-in space to be 100 feet less than its length. find the expressions to represent the length and width of the fenced section of the field

If rs 900 amounts to rs 1044 in 4 years, what sum will amount to 1368 in 3 1/2 years at the same rate