What role does substitution play when determining whether or not given value is a solution to an equation or an inequality?

The water has been on the stove y=9.5x+62.1 after how many minutes will the tempature be 138.1 f

The weights of players in a basketball league are distributed normally. the distance (d) of each player's weight (w) from the mean of 86 kilograms was computed as follows: d = |w - 86| if d is greater than 7 for approximately 5% of the players, what is the approximate standard deviation of the players' weights? a. 1.75 kilograms b. 3.5 kilograms c. 4.3 kilograms d. 7 kilograms

Iwill give ! if m∠a=59 and m∠3=81°, what is m∠b? m∠b= _[blank]_°