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I NEED HELP NOW...........NO LINKS AND TROLLING PLS

after being rearranged and simplified, which equation could be solved using the quadratic formula


A. 4x+2=0


B. 3x2-4=3x^2-4x


C. 2x=32


D. 5x^2+8x-12=2x2-x

User Rsz
by
2.3k points

2 Answers

10 votes
10 votes

Option D

  • 5x²+8x-12=2x²-x
  • 5x²-2x²+8x+x-12=0
  • 3x²+9x-12=0
  • x²+3x-4=0

Now we can apply quadratic formula to find two zeros

User Morten OC
by
2.7k points
27 votes
27 votes

Answer:


\textsf{D.}\quad5x^2+8x-12=2x^2-x

Explanation:

Quadratic Formula


x=(-b \pm √(b^2-4ac) )/(2a)\quad\textsf{when}\:ax^2+bx+c=0

A linear equation in the form
y=mx+b cannot be solved using the quadratic formula, as it is not a quadratic equation.


\textsf{A.}\quad 4x + 2 = 0

This is a linear equation and therefore cannot be solved using the quadratic formula.


\begin{aligned}\textsf{B.}\quad 3x^2-4&=3x^2-4x\\\implies -4&=-4x\end{aligned}

This is a linear equation and therefore cannot be solved using the quadratic formula.


\textsf{C.}\quad 2x=32

This is a linear equation and therefore cannot be solved using the quadratic formula.


\textsf{D.}\quad5x^2+8x-12=2x^2-x


\implies 3x^2+9x-12=0

Therefore, this is a quadratic equation in the form
ax^2+bx+c=0 and therefore can be solved quadratic formula.

a = 3, b = 9 and c = -12

Inputting these into the quadratic formula and solving for x:


\begin{aligned}\implies x &=(-(9) \pm √((9)^2-4(3)(-12)))/(2(3))\\\\x& = (-9 \pm √(225))/(6)\\\\x& = (-9 \pm 15)/(6)\\\\x&=(6)/(6),(-24)/(6)\\\\x&=1, -4\end{aligned}

User Fariha
by
2.7k points
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