Answer:
2√2
Step-by-step explanation:
By using trigonometry,
sin 45° = x/4
x = 4sin 45°
x = 2√2
By using Pythagorean theorem,
Since you know that it is an isosceles triangle and it's also a right-angled triangle,
4² = x² + x²
16 = 2x²
x² = 8
x = √8
= 2√2
