Exercise 25 Page 78

According to the order of operations, expressions inside parentheses are evaluated first, followed by exponents, then multiplication and division, and finally addition and subtraction are evaluated last. We can use the acronym PEMDAS to help us remember the correct order! For the given expression, this means this means calculating the power before evaluating the quotient and finally subtracting. 2.85-6.2÷ 2^2Let's find the power! 2.85-6.2÷ 2^2= 2.85-6.2÷ 4 Now, let's divide! 6.2÷ 4 We will divide, multiply, subtract, and compare as many times as we need.

We found that 6.2÷ 4=1.55. With this in mind, we can continue with our subtraction! 2.85-6.2÷ 4 = 2.85- 1.55 Recall that subtracting a number is the same as adding its opposite! 2.85- 1.55=2.85+( - 1.55) Now, we can find the sum of two numbers with different signs. We can do so by subtracting the lesser absolute value from the greater absolute value. Then, we will use the sign of the number with the greater absolute value. First, we can calculate the absolute value of the numbers. | 2.85|=2.85and| - 1.55|=1.55 Notice that | 2.85| is greater than | - 1.55|. This means that we should subtract | - 1.55| from | 2.85|. Let's do it!

| 2.85|-| - 1.55|

AbsPos

|2.85|=2.85

2.85-|- 1.55|

AbsNeg

|-1.55|=1.55

2.85-1.55

SubTerm

Subtract term

1.3

Recall that the number with the greater absolute value has a positive sign. This means that our numerator is a positive number, 1.3.