# How do you evaluate \sqrt { 25} - 9\cdot 2^ { 3}?

##### 1 Answer
Jan 2, 2017

The answer is $- 67$.

#### Explanation:

Order of operations precedence rules say to evaluate the power ${2}^{3}$ before multiplying it by 9, so $9 \cdot {2}^{3} = 9 \cdot 8 = 72$.

Since $\sqrt{25} = 5$ (take just the positive square root when you see this symbol in this context), it follows that $\sqrt{25} - 9 \cdot {2}^{3} = 5 - 72 = - 67$.