Question

Prove = (3x + 7) ^ 2 - 42x - 9x ^ 2 + 49​

Answer 1

Answer:

Step-by-step explanation:

x=7/3=2.333

The first term is,  9x2  its coefficient is  9 .

The middle term is,  -42x  its coefficient is  -42 .

The last term, "the constant", is  +49  

Step-1 : Multiply the coefficient of the first term by the constant   9 • 49 = 441  

Step-2 : Find two factors of  441  whose sum equals the coefficient of the middle term, which is   -42 .

     -441    +    -1    =    -442  

     -147    +    -3    =    -150  

     -63    +    -7    =    -70  

     -49    +    -9    =    -58  

     -21    +    -21    =    -42