Question

Dau coroana daca ma ajutati sa fac exercitile astea !!!​

Answer 1

1.6a-9b=6(3x-2)-9(2x-3)

6a-9b= 18x-12-18x+27

6a-9b=15

2.(2x+13)^2=4x^2-ax+169

4x^2+52x+169=4x^2-ax+169

4x^2-4x^2+52x-ax+169-169=0

52x-ax=0

x(52-a)=0

52-a=0

-a=-52

a=52

3.=2(x+1)^2+2(x-1)^2-(2x-3)(2x+3)

=2(x^2+x+1)+2(x^2-x+1)-[(2x)^2-3^2]

=2x^2+2x+2+2x^2-2x+2-4x^2+9

=2+2+9

=13