Math  Please Check My Answers
posted by Brady .
Please help me by checking the following answers for me(There are 3 problems that I need someone to check).
3. A student is attempting to solve the equation below for the variable x. Which of the statements below best applies to the mathematical work shown?
Given √(4x6)=12, I square both sides, so (√4x)^26=〖12〗^2, or 4x 6 = 144. I can then solve for x, yielding x = 37 1/2 as my final answer.
A. The student did not correctly square both sides of the equation.  (This is my second answer.)
B. The student did not properly isolate the variable after squaring both sides of the equation.
C. The student omitted a negative solution to the equation.
D. The mathematical work is correct.  (I know it is not this because I got it wrong.)
4. Solve for x.
〖5x〗^2+3=122
A. No solution.  (This is my second answer.)
B. 5  (I know it is not the answer because I got it wrong.)
C. ±5
D. ±25
9. The acceleration of an object can be described by the equation a= 2d/t^2, where a is acceleration, d is the distance, and t is time. If an object accelerates at a rate of 2 m/s^2 for 10 meters, what is the total time elapsed?
A. 1/10 seconds  (This is my second answer.)
B. √(1/10) seconds
C. √10 seconds
D. 10 seconds  (I know it is not answer because I got it wrong.)
Please check them to see if I am correct. Any help will really be appreciated! :)

For 3, I don't see anything wrong with the work unless the initial equation is supposed to be sqrt(4x)6=12 in which case the squaring wasn't done correctly, but based off what I see there D IS correct. For 4, A is the correct answer. You cannot take the square root of a ve number. For 5, the correct answer is C. you have 2(10)/t^2=2, which leads to 20=2t^2. Then, 10=t^2 which therefore leaves t=sqrt(10)

Thank you, Dayton! :)