How do you write 13 and ten hundredths

Charles is on a 8 1/2 mile bike ride. he stops for a rest after he’s gone 5 2/5 miles. how much farther does he still have to go?

In trapezoid efgh, m∠hef=(4x2+16)∘ and m∠gfe=(5x2+12)∘. find the value of x so that efgh is isosceles.

One line passes through (-7,-4) and (5,4) . another line passes through the point (-4,6) and (6,-9)