RN = 5cm, ∠R = ∠N = 45°.

Step -1:
Draw a rough sketch of a triangle and label it with the given measurements.
Step -2:
Draw a line segment RN of length 5cm.
Step -3:
Draw a ray \(\overrightarrow {RX}\) making an angle 45° at R.
Step -4:
Draw a ray \(\overrightarrow {NY}\) making an angle 45° at N.
Step -5:
Mark the intersecting point of the two rays as U. ΔRUN is the required triangle
∠U = 90°, RU = UN = 3.5 cm.
∴ The triangle is an isosceles right angled triangle.