-3√45 + 3√20 = -3√(9 · 5) + 3√(4 · 5) =
= -3√(3² · 5) + 3√(2² · 5) =
= -3 · 3√5 + 3 · 2√5 =
= -9√5 + 6√5 = -3√5 ← the end
Answer:
y=90 degree
Step-by-step explanation:
bcz this triangle is drawn in the semi-circle and the greatest angle of triangle in a semi-circle is always right angle.