Question

if a+b+c =10 and ab+bc+ca=15 find (a+b+c)(a^2+b^2+c^2-ab-bc-ca)

Answer 1

550 is the answer please mark as brainlist

Answer 2

Hi ,

a + b + c = 10 ----( 1 )

ab + bc + ca = 15 ----( 2 )

2( ab + bc + can ) = 30 ---( 3 )

a² + b² + c² = ( a +b+c)²-2( ab+bc+ca)

= 10² - 30

= 70 --- ( 4 )

Now ,

( a +b+c)[a²+b²+c²-(ab+bc+ca)]

= 10 [ 70 - 15]

= 10 × 55

= 550

I hope this helps you.

: )