4x^2+25=4x^2=-25=x^2=-25/4 has no solution. because, negative number do not live under radical except complex number
Joel = j, Mark = m, Sandra = s
j + m + s = 120
m = 3j
j = 1/2 s --> s = 2j
plug in (substitute) each letter to make it in terms of only j: j + m + s = 120
j + 3j + 2j = 120
6j = 120
6j/6 = 120/6
j = 20
now plug in for the j & s equation:
s = 2j = 2(20) = 40
Therefore Sandra has 40 coins!
Answer:
Solution set = {-12, 12}
Step-by-step explanation:
Start by dividing both sides of the given equation by negative one, to get rid of the negative signs on both sides:

Now we consider the two possible cases:
1) The expression inside the absolute value symbol is a positive number, then :

and replacing it in the equation, this becomes:

which is our first answer.
2) The expression inside the absolute value symbol is a negative number, then :

and replacing it in the equation, this becomes:

which is our second possible answer.
Then the set of solutions is: {-12, 12}
Right next to the zero van I heht brainleist please