which equations are true for x = -2 and x = 2? select two options\n□x² - 4 = 0\n□x² = -4\n□3x² + 12 =…
which equations are true for x = -2 and x = 2? select two options\n□x² - 4 = 0\n□x² = -4\n□3x² + 12 = 0\n□4x² = 16\n□2(x - 2)² = 0
Answer
Explanation:
Step1: Check $x^{2}-4 = 0$
Substitute $x=-2$: $(-2)^{2}-4=4 - 4=0$. Substitute $x = 2$: $2^{2}-4=4 - 4=0$.
Step2: Check $x^{2}=-4$
Substitute $x=-2$: $(-2)^{2}=4\neq - 4$. Substitute $x = 2$: $2^{2}=4\neq - 4$.
Step3: Check $3x^{2}+12 = 0$
Rewrite as $3x^{2}=-12$, then $x^{2}=-4$. Substitute $x=-2$: $(-2)^{2}=4\neq - 4$. Substitute $x = 2$: $2^{2}=4\neq - 4$.
Step4: Check $4x^{2}=16$
Divide both sides by 4 to get $x^{2}=4$. Substitute $x=-2$: $(-2)^{2}=4$. Substitute $x = 2$: $2^{2}=4$.
Step5: Check $2(x - 2)^{2}=0$
When $x=-2$, $2(-2 - 2)^{2}=2\times(-4)^{2}=2\times16 = 32\neq0$. When $x = 2$, $2(2 - 2)^{2}=0$.
Answer:
$x^{2}-4 = 0$, $4x^{2}=16$