Let sqrt = square root for short.
7(sqrt{3x - 4}) + 7 = 35
This is a radical equation.
The goal is to isolate the radical on one side of the equation.
Subtract 7 from both sides as step one.
Doing so, we get this: 7(sqrt{3x - 4} = 28
We now divide both sides by 7. This will isolate the radical on the left side.
sqrt{3x - 4} = 28/7
sqrt{3x - 4} = 4
We now square both sides. This is remove the radical from the left side of the equation.
(sqrt{3x - 4})^2 = (4)^2
3x - 4 = 16
3x = 16 + 4
3x = 20
x = 20/3
Is this the true value of x?
We must prove this is the right value of x by plugging 20/3 for x in the original question given. Afterward, we simplify the radical equation.
The idea is get the same answer on both sides.
Let x = 20/3
7(sqrt{3(20/3) - 4}) + 7 = 35
7(sqrt{20 - 4}) + 7 = 35
7(sqrt{16}) + 7 = 35
7(4) + 7 = 35
28 + 7 = 35
35 = 35...It checks!!!
So, the right answer for x is 20/3.