Solve by extracting square roots.
-x $x ^ { 2 } - 3 x$
A) $9 ; ( x - 3 ) ^ { 2 }$
B) $\frac { 9 } { 4 } ; \left( x + \frac { 3 } { 2 } \right) ^ { 2 }$
C) $\frac { 9 } { 4 } ; \left( x - \frac { 3 } { 2 } \right) ^ { 2 }$
D) $0 ; \left( x - \frac { 3 } { 2 } \right) ^ { 2 }$

Question

Quizplus · Accepted Answer

We can factor out an x from the expression: x(x-3x) = x^2 - 3x^2. Then we can extract a square root: √(x^2 - 3x^2) = √(x^2(1-3)) = √(x^2(-2)) = √(-2)(x^2) = i√2x. The only option with i√2x as a possible answer is C: √(9/4) ; (x-3/2)^2 = |3/2| ; (x-3/2)^2 = (3/2-x)^2 = i√2x, which simplifies to x = 3/2 ± i√2/2.

Solve by Extracting Square Roots x2−3xx ^ { 2 } - 3 xx2−3x

Solve by Extracting Square Roots $x ^ { 2 } - 3 x$