Answer:
15 units
Step-by-step explanation:
<u><em>The picture of the question in the attached figure</em></u>
we know that
In the right triangle ABC
Applying the Pythagorean Theorem

we have

substitute the given values

solve for BC

Answer:
y = 3
Step-by-step explanation:
According to Euclidian theorem:
y^2 = 3*(12+3)
y^2 = 45 find the root of both sides
y = 3