Concept: The question tests on the application skills in inequality
on squaring both sides:
x^2 + 10x + 25 ≤ 4x^2 − 20x + 25
=>-3x^2 + 30x <=0
=> -x^2 +10x < = 0
Multiply with -1 and flip the sign
=>x^2−10 x ≥ 0
=> x(x−10)≥0 hence the critical points are 0 and 10.
Both are of same sign.
Using the wavy curve approach, x<=smallest critical point or x>=greatest critical point in this case.
Refer to wavy curve approach explained in the session o Inequality
=>x≤0 or x≥ 10