math
posted by steve .
if triangles abc and xyz are congruent. angle a is one half the size of angle b. angle y is 90 degrees. angle c and angle z are both 45 degrees. what is the measure of angle a?

From the information, the three angles are 904545.
If a is half of b, then b=90° and a=45°.
See if you can figure out the rest.