Answer:
Um for what test?
Step-by-step explanation:
X is 90°
A triangles angles add up to 180° so
180 - 47 - 90 = y
180 - 137 = y
y = 43°
In order to derive the base of a triangle from its area, you need its height as well.
In fact, if we solve the area formula for the base, we have

So, the base length would be

where h is the height relative to the base you're interested in.