Evaluate e-1/2 f when e = 15 and f = 2

Proving the parallelogram diagonal theoremgiven abcd is a parralelogam, diagnals ac and bd intersect at eprove ae is conruent to ce and be is congruent to de

In an isosceles triangle, the vertex angle is 112 degrees. what is the measure of each base. a.34 b.24 c.44 d.54

Cos^2x+cos^2(120°+x)+cos^2(120°-x)i need this asap. pls me