For the equation 27x = 3x+7, which of the following is the solution for x?
- No solution
Incorrect. You may consider getting the same base first.
- x = 3.5
Correct! You solved the equations correctly.
- x = 7 4
Incorrect. After setting exponents equal, subtract x from both sides to isolate variable.
- x = 2
Incorrect. Check solution.
Suzanne wants to solve the equation below by finding the same bases.
42x = 8x-1
Which of the following could be the first step to solve this equation using the same bases?
- 22x+2 = 2x-1+2
Incorrect. When raising a power to a power, multiply the exponents.
- 84x = 8x-1
Incorrect. 42 ≠ 82
- 42x = 42(x-1)
Incorrect. 42 ≠ 8
- 24x = 23(x-1)
Correct! You substituted 22 for 4 and 23 for 8.
Roy needs help solving the equation below. He did the first step and then got stuck.
721 = 23x
log721 = log23x
Which of the following is the next step to solve the equation?
- log 721 = (3x)log 2
Correct! Since there was a power raised to a higher power, you multiplied.
- log 721 = 21log 3x
Incorrect. For a power to a power, multiply. This one transposed the numbers.
- (3x)log 721 = log 2
Incorrect. For a power to a power, multiply. This one multiplied 3x to the other side.
- (2)log 721= log 3x
Incorrect. For a power to a power, multiply. This one transposed the numbers and multiplied to wrong side.
For the equation 20,000 = 10,000(1.045)t, which of the following is a solution for t?
- t = 1.1
Incorrect. Isolate the exponential term first.
- t = 15.7
Correct! You solved correctly.
- t = 0.06
Incorrect. To isolate variable, divide by coefficient.
- t = 0.01
Incorrect. To isolate variable, divide by coefficient.