Question

Solve by factorlsation method and fromulamethod

$2x2 + 4 - 6 = 0$

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Answer 1

Answer:

Step-by-step explanation:

Suppose we are asked to solve the quadratic equation (x-1)(x+3)=0(x−1)(x+3)=0left parenthesis, x, minus, 1, right parenthesis, left parenthesis, x, plus, 3, right parenthesis, equals, 0. [Why is this a quadratic equation?]

This is a product of two expressions that is equal to zero. Note that any xxx value that makes either (x-1)(x−1)left parenthesis, x, minus, 1, right parenthesis or (x+3)(x+3)left parenthesis, x, plus, 3, right parenthesis zero, will make their product zero.

\begin{aligned} (x-1)&(x+3)=0 \\\\ \swarrow\quad&\quad\searrow \\\\ x-1=0\quad&\quad x+3=0 \\\\ x=1\quad&\quad x=-3 \end{aligned}  

(x−1)

↙

x−1=0

x=1

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(x+3)=0

↘

x+3=0

x=−3

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Substituting either x=1x=1x, equals, 1 or x=-3x=−3x, equals, minus, 3 into the equation will result in the true statement 0=00=00, equals, 0, so they are both solutions to the equation.