Question

Guys pls due is tomorrow I need both answers with explanation plzplz

Answer 1

Answer:

Step-by-step explanation:

9.4+1+9=14-2+3+6=14-11=3

7x2+5xy-9y2+4y2-3x2-6xy+-4x2+xy+5y2=4x2-4x2=0,-xy+xy=0,-5y2+5y2=0 so and 0+0+0=o so that proves hope it helps plz mark my answer as brainliest thanks in advance

Answer 2

Answer:

Ans 9) x= -2, y= -1, z=3

x^2+ y^2+z^2-xy-yz-zx

Substituting the values

(-2)^2+ (-1)^2+ (3)^2 - (-2)(-1) - (-1)(3) - (3)(-2)

[4 + 1 + 9] - [ 2 - (-3) - (-6)]

14 - [2 +3 +6]

14- 11

Ans = 3

Ans10) p= 7x^2 + 5xy - 9y^2 , q= 4y^2 - 3x^2 - 6xy , r= -4x^2+ xy+ 5y^2

To prove : p+q+r=0

[ 7x^2 + 5xy - 9y^2] + [ 4y^2 - 3x^2 - 6xy] +  [-4x^2+ xy+ 5y^2] = 0

7x^2 + 5xy - 9y^2 + 4y^2 - 3x^2 - 6xy -4x^2+ xy+ 5y^2=0

7x^2- 3x^2- 4x^2 +5xy - 6xy +xy - 9y^2 + 4y^2+5y^2 = 0

7x^2 - 7x^2 + 6xy - 6xy - 9y^2 + 9y^2 =0

0 = 0

Hence, Proved

Hope it helps you !!