Question

I need help on num.1 great explanation=5 stars , I am writing this down in my notebook

Answer 1

We want to evaluate the following expression

`(d+e\colon8)^2-10f`

Using the following values

`\begin{gathered} d=18 \\ e=56 \\ f=2 \end{gathered}`

Before we start calculating, first, we just need to plug those values in our expression. In order to do that, we need to substitute the corresponding values with the corresponding letters. For example, d = 18, then, we need to substitute the d in the expression by 18.

After those substitutions, we have the following expression

`(18+56\colon8)^2-10*2`

Now, we need to do the operations in a certain order. First, we need to solve the operations inside of the parenthesis. Inside of the parenthesis we have two operations, an addition and a division. The order of the four operations(by the first we should do to the last) is: multiplication and division, addition and subtraction. Then, we should start with the division.

`\begin{gathered} 56\colon8=7 \\ \Rightarrow(18+56\colon8)^2-10*2=(18+7)^2-10*2 \end{gathered}`

Now, we can do the other operation inside of the parenthesis.

`\begin{gathered} 18+7=25 \\ \Rightarrow(18+7)^2-10*2=(25)^2-10*2 \end{gathered}`

Now, we should do the exponential, then the multiplication, and by last the subtraction.

`\begin{gathered} 25^2=625 \\ \Rightarrow(25)^2-10*2=625-10*2 \\ 10*2=20 \\ \Rightarrow625-10*2=625-20=605 \end{gathered}`

And this is our final answer. This expression evaluated with the given values is equal to 605.