In Exercises 85–96, simplify each algebraic expression. 5(3x+4)−4

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Welcome back. I'm so glad you're here. We've got an expression and we get to simplify it. And we have eight minus two times parentheses X plus five and parentheses? Great. Now where do we start? Well we recall from previous lessons that we have the acronym penned us to help remind us of the order of operations. So we start with parentheses and then we'll work with exponents then multiplication and division from left to right and then addition and subtraction from left to right. So do we have any parentheses? Yes we do. We have this parentheses X plus five. But there is one caveat here with addition and subtraction. We can only add and subtract like terms. And so we've got the X plus the five. That the addition operation in here but they're not like terms. So we can add them. We can't do the work inside the parentheses here. So we ask ourselves if the parentheses serve a second function. Sometimes parentheses indicate multiplication when there's a number squished up in front of it. And that means we're going to distribute that number to multiply it by each of the numbers inside. Yes we have that negative two and it is going to indicate multiplication or distribution here. And so the only other operation is subtraction before that. Which one do we do first? Well multiplication comes before subtraction in the order of operations. So let's distribute that negative two. We've got negative two times X which is negative two X. And negative two times five which is negative 10. Then we'll bring down what's left. Which is that eight out in front. So now the only operations we've got going on here are subtraction and subtraction. And as we said before we have to subtract like terms the like terms here are eight minus 10. So we've got eight minus 10 which equals negative two. So we can write negative two and bring down the other part which is negative two X. So we've got negative two x minus two. We look at our answer choices and that matches with answer choice. D. While done we'll catch you on the next one.

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