basic algebra

Question

Simplify the algebraic expression following order of operations: (x y) +10wz ifx=5,y=10,w=-1,andz=4.

Answer 1

Joe, Michael's answer is correct, but I thought I would offer some explanation since I am not familiar with your background in math and in case there are others who come on here wondering the same thing as you.

 

Essentially, what you are doing in this problem is substituting or "plugging in" 5 where ever there is an x, 10 where the y is, -1 where the w is, and 4 where the z is. This is where Michael gets (5*10)+10(-1)(4) from.

 

Then you will simplify using the order of operations. The order of operations tells you what to do first. When you have two of the same operations you typically will go left to right. Here are the order of operations with parentheses coming first:

 

Parentheses

Exponents

Multiplication

Division

Addition

Subtraction

 

Michael does the 5*10 first because it is in parentheses. Then the remaining operations are the addition and the 10 times -1 times 4. Because multiplication comes before addition, we need to multiply the last three numbers first. You can multiply in any order. Michael chose to multiply the -1 and 4 first. So it goes from 10*-1*4 to 10*-4 to -40. The only remaining step is adding 50 + -40. Since adding a negative is the same as subtracting, Michael changed it to 50-40 to get 10.

 

Answer 2

(xy)+10wz =

 

(5*10)+10(-1)(4) =

 

50+10(-4) =

 

50 - 40 =

 

10