SPECIAL RIGHT TRIANGLES 45-45-90 I NEED HELP ASAP (no rocky lol) and ignore that sentence at the bottom

The perimeter of a movie screen is 54 meters. the screen is 18 meters wide. how tall is it?

When x = 3 and y = 5, by how much does the value of 3x2 – 2y exceed the value of 2x2 – 3y ?

If two angles of a triangle have equal measures and the third angle measures 90°, what are the angle measures of the triangle? a. 60°, 60°, 60° b. 45°, 90°, 90° c. 30°, 30°, 90° d. 45°, 45°, 90°