Q8 of 95 Page 93

Find the value of the expression (9x2 + 24x + 16), when x = 12.

Given,


(9x2 + 24x + 16)


x = 12


So, we can also write it as;


= (3x)2 + 2(3x)(4) + (4)2


→ By the formula (a + b)2 we get,


= (3x + 4)2


= [3 (12) + 4]2


= [36 + 4]2


= [40]2 = 1600


Hence the value of the expression is 1600 when x =12.


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