Question

a+b = 15, a-b = 7 find the value of 14ab(a^2+b^2)​

Answer 1

Answer:

Step-by-step explanation:

$a + b = 15\\ a - b = 7$

Substitute a with with b + 7 in equation 1 :

$b + 7 + b = 15$

$2b + 7 = 15\\2b = 15-7\\2b = 8\\b = 8/2 = 4$

b = 4

Substitute b with 4 in equation 2 :

$a - 4 = 7\\a = 7 + 4 = 11$

a = 11

Now, substitute a and b with 11 and 4, respectively in the equation :

$14ab(a^{2} + b^{2})$

$14(11)(4)(11^{2} + 4^{2} )$

$14(44)(121 + 16)\\14(44)(137)\\84392$

Therefore, the answer is 84392.