Home
Class 7
MATHS
If 2^(2y)=(1)/(4) and 3^(4x)=(1)/(81) th...

If `2^(2y)=(1)/(4) and 3^(4x)=(1)/(81)` then x+y ____

A

0

B

`-2`

C

1

D

2

Text Solution

AI Generated Solution

The correct Answer is:
To solve the equations given in the problem, we will follow these steps: ### Step 1: Solve for y from the first equation We start with the equation: \[ 2^{2y} = \frac{1}{4} \] We can express \( \frac{1}{4} \) as a power of 2: \[ \frac{1}{4} = 2^{-2} \] Now we have: \[ 2^{2y} = 2^{-2} \] Since the bases are the same, we can set the exponents equal to each other: \[ 2y = -2 \] Now, divide both sides by 2 to solve for y: \[ y = \frac{-2}{2} = -1 \] ### Step 2: Solve for x from the second equation Now we consider the second equation: \[ 3^{4x} = \frac{1}{81} \] We can express \( \frac{1}{81} \) as a power of 3: \[ \frac{1}{81} = 3^{-4} \] Now we have: \[ 3^{4x} = 3^{-4} \] Again, since the bases are the same, we can set the exponents equal: \[ 4x = -4 \] Now, divide both sides by 4 to solve for x: \[ x = \frac{-4}{4} = -1 \] ### Step 3: Calculate x + y Now that we have the values of x and y: \[ x = -1 \] \[ y = -1 \] We can find \( x + y \): \[ x + y = -1 + (-1) = -2 \] ### Final Answer Thus, the value of \( x + y \) is: \[ \boxed{-2} \] ---
Promotional Banner

Similar Questions

Explore conceptually related problems

If x^((1)/(4)) + x^((-1)/(4))=2 , then what is the value of x^(81) + ((1)/(x^(81))) ?

If 3^(4x)=(81)^(-1) and 10^((1)/(y))=0.0001, find the value of 2^(-x+4y) and 10^((1)/(y))=0.0001, find the

If x = (2)/(3) and y = (3)/(4), then a rational number (x – y) ^(-1) + (x ^(-1) – y ^(-1)) is equal to