If$△\mathrm{ABC}$is a right-angled triangle such that $\angle \mathrm{B}$ $= {90}^0$, (AB + BC) – AC = $20$ cm and perimeter of $△\mathrm{ABC}$ =$60$ cm, then area of the triangle (in ${\mathrm{cm}}^2$) is.

In the diagram given below RT $\perp$PQ. S is a point on QR such that: $\angle$QPS = 40°, $\angle$TRQ = 30°, then $\angle$PSQ = ?

In the given diagram if AB||CD||EF then which of the given options is true.

In the given figure PR = QR = PS, $\angle$ZPSR = X, $\angle$TPS =90° then x = ?

In the given diagram two concentric circles with centre O are shown. If $\angle$$\mathrm{AOB} = 120°$ Then $\angle$$\mathrm{OAP} =$

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In the question find $\angle \mathrm{BAO}$.