5. a^2 + b^2 = c^2...where a and b are the legs and c is the hypotenuse
7^2 + 10^2 = c^2
49 + 100 =c^2
149 = c^2....take square root of both sides, eliminating the ^2
sq rt 149 = c
12.21 = c.....so the approximate length of 3rd side is 12 m
6. x = number of books bought
7. m < 2 + m < 8 = 180
8. 1000 = 400 + 24x
1000 - 400 = 24x
600 = 24x
600/24 = x
25 = x <=== 25 months he will have spent $ 1000
