The width is 11.
You can get this by setting up an equation that says:
x (x - 3) = 154
Then distribute and use the quadratic equation to solve.
So you start by dividing 6 out of the expression and you get 6(4-3)
Let the unknown number be y.
We can list the equation out by the clues given.
5y + 12 = 52
Then solve this as simple algebra!
Shift +12 to the other side and be - 12
5y = 52-12
5y = 40
Shift x5 to the other side and be ÷5
y = 40 / 5
y = 8
Therfore the unknown number is 8.
Answer:
b = 29.0, A = 123.9°, C = 20.1°