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3 votes
PLZ HELP!

Rocky simplified an expression in three steps, as shown:


Which is the first incorrect step and why?

Step 1, all the exponents are increased by 2
Step 1, all the exponents are multiplied by 2
Step 2, the exponents in the denominator are added during multiplication
Step 3, the exponents of the same base are added during division

PLZ HELP! Rocky simplified an expression in three steps, as shown: Which is the first-example-1
User Kelsi
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2 Answers

6 votes
Step 3 is wrong because when dividing exponents you subtract them x^-10 would be multiplying by x^-12 making it x^-10-12 and that would be x^-22 same applies for the y exponents
User Warren Weckesser
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6.4k points
6 votes

Answer:

Step 3: exponents of the same base are added during division.

Explanation:

We have been an expression and steps used to solve the expression. We are asked to find the 1st incorrect step.

Expression:
((x^(-5)y^2)/(yx^3\cdot x^3y^(-5)))^2

Step 1: We will distribute the exponent as:


(x^(-5* 2)y^(2* 2))/(y^(1* 2)x^(3* 2)\cdot x^(3* 2)y^(-5* 2))


(x^(-10)y^(4))/(y^(2)x^(6)\cdot x^(6)y^(-10))

Step 2: Combine the exponents in denominator.


(x^(-10)y^(4))/(y^(2+(-10))x^(6+6))


(x^(-10)y^(4))/(y^(-8)x^(12))

Step 3: Use quotient rule of exponents
(a^m)/(a^n)=a^(m-n).


(x^(-10)y^(4))/(y^(-8)x^(12))=x^((-10-12))y^(4-(-8))


(x^(-10)y^(4))/(y^(-8)x^(12))=x^((-22))y^(4+8)


(x^(-10)y^(4))/(y^(-8)x^(12))=x^((-22))y^(12)

Therefore, the student made a mistake in 3rd step as the exponents of the same base are added during division.

User Shanakay
by
7.7k points
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