The perimeter of the triangle with the sides measuring 15 inches, 18 inches, and 7 inches is 40 inches. if you wanted to construct a similar triangle with a perimeter of 50 inches, what would be the length of the shortest side of the triangle? show your work.

Express the following as a function of a single angle, cos(60) cos(-20) - sin(60) sin(-20)

Which statement justifies why angle ebc measures 90?

If m∠abc = 70°, what is m∠abd? justify your reasoning.  using the addition property of equality, 40 + 70 = 110, so m∠abd = 110°.  using the subtraction property of equality, 70 − 30 = 40, so m∠abd = 30°.  using the angle addition postulate, 40 + m∠abd = 70. so, m∠abd = 30° using the subtraction property of equality.  using the angle addition postulate, 40 + 70 = m∠abd. so, m∠abd = 110° using the addition property of equality.