I am using "x" but alphabet letter does not matter.
#9
Words: x is greater than or equal to -4
Algebra: x ≥ -4
Possible solutions: 0,1,2
#13
Words: x is greater than 0
Algebra: x > 0
Possible solutions: 1,2,3
90 ÷ 2 is the same as 1/2 of 90.
Either way you get 45.
Let x represent the length of the shortest side. Then the longest side is
... 2x -7 . . . . . . 7 ft shorter than twice the shortest side
and the 3rd side is
... x +2 . . . . . . 2 ft longer than the shortest side.
The perimeter is the sum of the side lengths,
... x + (2x -7) + (x +2) = 59 . . . . . the given perimeter length
... 4x -5 = 59 . . . . collect terms
... 4x = 64 . . . . . . add 5
... x = 16 . . . . . . . . divide by 4
Then the other sides are
... 2×16 - 7 = 25 . . . . . longest side
... 16 +2 = 18 . . . . . . . . third side
The side lengths are 16 ft, 18 ft, and 25 ft.
You would multiply 10 times \pi (3.14)
and get 31.40 cm squared
