5). (2 points each) Find X for each of these triangle problems. First write down the equation for the sum of the angles in a triangle, then solve it. I will write the first equation for you.


a).
Equation: 2X + X + 90 = 180


X = _______

b).
Equation:______________________

X = _______

c).
Equation:______________________

X = _______

d).
Equation:______________________

X = _______