Solve the Algebraic Fraction: Simplify 78xy^5 Over 3x^5 Times 4yx Over 5y^4

Algebraic Fractions with Negative Exponents

Solve:

78xy53x54yx5y4= \frac{78xy^5}{3x^5}\cdot\frac{4yx}{5y^4}=

❤️ Continue Your Math Journey!

We have hundreds of course questions with personalized recommendations + Account 100% premium

Step-by-step video solution

Watch the teacher solve the problem with clear explanations
00:00 Simplify the following problem
00:03 Make sure to multiply the numerator by numerator and the denominator by the denominator
00:23 Let's calculate 78 times 4
00:31 Let's calculate 5 times 3
00:37 When multiplying powers with equal bases
00:40 The power of the result equals the sum of the powers
00:43 We'll apply this formula to our exercise and add the powers together
00:57 When dividing powers with equal bases
01:00 The power of the result equals the difference of the powers
01:06 We'll apply this formula to our exercise and subtract the powers
01:20 This is the solution

Step-by-step written solution

Follow each step carefully to understand the complete solution
1

Understand the problem

Solve:

78xy53x54yx5y4= \frac{78xy^5}{3x^5}\cdot\frac{4yx}{5y^4}=

2

Step-by-step solution

To solve the problem, we'll follow these steps:

  • Step 1: Multiply the fractions 78xy53x5\frac{78xy^5}{3x^5} and 4yx5y4\frac{4yx}{5y^4}.

  • Step 2: Simplify the coefficients and apply exponent rules to the variables.

  • Step 3: Identify the correct multiple-choice option matching the simplified expression.

Now, let's work through each step in detail:

Step 1: Multiply the Fractions

We multiply the numerators together and the denominators together:

78xy53x54yx5y4=78xy54yx3x55y4 \frac{78xy^5}{3x^5} \cdot \frac{4yx}{5y^4} = \frac{78xy^5 \cdot 4yx}{3x^5 \cdot 5y^4}

Simplifying, we have:

=784xxy5y35x5y4 = \frac{78 \cdot 4 \cdot x \cdot x \cdot y^5 \cdot y}{3 \cdot 5 \cdot x^5 \cdot y^4}

Step 2: Simplify the Expression

Simplify the coefficients:

784=312 78 \cdot 4 = 312 and 35=15 3 \cdot 5 = 15

Combine the coefficients:

31215 \frac{312}{15}

Now simplify the variables using exponent rules:

Combine powers of the same base:

xx=x2 x \cdot x = x^2

The numerator becomes:

312x2y6 312 \cdot x^2 \cdot y^6

The denominator according to x2xn=x2n\frac{x^2}{x^n} = x^{2-n}, given,

15x5y4 15 \cdot x^5 \cdot y^4

Simplifying the exponents:

x25=x3 x^{2-5} = x^{-3} and y64=y2 y^{6-4} = y^2

Thus,

312x3y215 \frac{312 \cdot x^{-3} \cdot y^2}{15}

Conclusion:

After simplifying the expression, the result is:

312x3y215 \frac{312\cdot x^{-3}\cdot y^2}{15}

Matching this with the multiple-choice options, the correct choice is option 3.

Therefore, the solution to the problem is 312x3y215 \frac{312\cdot x^{-3}\cdot y^2}{15} .

3

Final Answer

312x3y215 \frac{312\cdot x^{-3}\cdot y^2}{15}

Key Points to Remember

Essential concepts to master this topic
  • Multiplication Rule: Multiply numerators together and denominators together
  • Exponent Laws: x2÷x5=x25=x3 x^2 \div x^5 = x^{2-5} = x^{-3}
  • Verification: Check that coefficients and variable powers match answer choices ✓

Common Mistakes

Avoid these frequent errors
  • Adding exponents instead of subtracting when dividing
    Don't add exponents like x² × x⁵ = x⁷ when you have division = wrong powers! Division means subtracting exponents, not adding them. Always use x^a ÷ x^b = x^(a-b) for division of same variables.

Practice Quiz

Test your knowledge with interactive questions

Simplify the following equation:

\( \)\( 4^5\times4^5= \)

FAQ

Everything you need to know about this question

What does a negative exponent like x^(-3) mean?

+

A negative exponent means reciprocal! So x3=1x3 x^{-3} = \frac{1}{x^3} . It's perfectly normal to have negative exponents in your final answer.

Why do I multiply the fractions instead of adding them?

+

The problem shows a multiplication symbol (·) between the fractions, not addition. When multiplying fractions, you multiply straight across: numerator × numerator and denominator × denominator.

How do I handle all these variables (x and y) at once?

+

Treat each variable separately! Group all the x terms together and all the y terms together. Then apply exponent rules to each variable type independently.

Should I simplify 312/15 in my final answer?

+

Not necessarily! Looking at the answer choices, option 3 keeps it as 312x3y215 \frac{312 \cdot x^{-3} \cdot y^2}{15} . Sometimes the unsimplified form matches what's expected.

What if I get confused with so many steps?

+

Break it down: Step 1 - multiply fractions, Step 2 - simplify numbers (78×4 and 3×5), Step 3 - handle x variables, Step 4 - handle y variables. Take it one step at a time!

🌟 Unlock Your Math Potential

Get unlimited access to all 18 Exponents Rules questions, detailed video solutions, and personalized progress tracking.

📹

Unlimited Video Solutions

Step-by-step explanations for every problem

📊

Progress Analytics

Track your mastery across all topics

🚫

Ad-Free Learning

Focus on math without distractions

No credit card required • Cancel anytime

More Questions

Click on any question to see the complete solution with step-by-step explanations