Answer:
Step-by-step explanation:
This is a 45-45-90 triangle
D. 13 1/2
2/3 x -2 = 7
2/3 x -2 + 2 = 7 + 2
2/3 x = 9
x = 9 (3/2)
x = 27/2
x = 13 1/2
sqrt. 244
a^2 + b^2 =c^2
10^2 + 12^2 =244
c^2 =244
c= sqrt. 244
4 inches
the middle number is 6 and the distance from 99.7 from the middle is 3 standard deviations. 12/3 =4
