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How do i solve 3k(squared)-14k-49.... like how do i factor it out

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4 Answers

There are two ways you can solve quadratic equation:
 1. To solve quadratic equation is means to find its zeros. Use the Quadratic formula. You will find two real solutions or zeros: 7 and -7/3. 
2. By factoring: 
first, multiply 3 by 49=147
next find factors of 147 that sum of factors is -14. It is -21 and 7.
next, 3k^2-21k+7k -49, next, (3k^2 -21k)+(7k-49)=3k(k-7)+7(k-7)=(k-7)(3k+7)
(k-7)(3k+7)=0, zero product property, k-7=0, k=7; 3k+7=0, k=-7/3.
Trial and error or the quadratic equation are the only 2 ways. You know the first terms in each set of parentheses will be 3k and k respectively. So your factored equation will look like this: (3k + ?)(k-?). You know the plus and the minus go in those places because the constant B is negative. (Ax2 + Bx + C is the form of your formula, also known as quadratic form or standard form of a quadratic... just to explain the B constant.)