Can someone please explain how to do systems of equations with substitution

Which best describes the construction of a triangle if given the segment lengths of 2 cm, 3 cm, and 5 cm? a) unique triangle b) cannot be determined c) triangle not possible d) more than one triangle

Sioux co. replaced the roof on its existing building, therefore increasing the building's life by 10 years. the cost of the roof is considered a(n):

Atown recently dismissed 5 employees in order to meet their new budget reductions. the town had 5 employees over 50 years of age and 19 under 50. if the dismissed employees were selected at random, what is the probability that exactly 2 employees were over 50? express your answer as a fraction or a decimal number rounded to four decimal places.