Answer:
5) 5
6) [tex]2(x+3)(x+4)[/tex]
Zeros: [tex]x_1=-3\\x_2=-4[/tex]
7) [tex]x^{2}+11x-180=0\\(x+20)(x-9)=0[/tex]
Step-by-step explanation:
5) You can factor the quadratic equation [tex]-t^{2}-t+30[/tex] to solve it:
[tex]-(x-5)(x+6)=0[/tex]
Then you obtain:
[tex]x_1=5\\x_2=-6[/tex]
Choose the positive result.
6) You can factor out 2:
[tex]2(x^{2}+7x+12)=0[/tex]
Factor the expression. Find the numbers that sum 7 and the their product is 12. These would be 3 and 4:
[tex]2(x+3)(x+4)[/tex]
The zeros are:
[tex]x_1=-3\\x_2=-4[/tex]
7) If you factor the quadratic equation [tex]x^{2}+11x-180=0[/tex] you obtain:
[tex](x+20)(x-9)=0[/tex]
And the zeros are:
[tex]x_1=-20\\x_2=9[/tex]
Therefore, the answers are the options 3 and 4:
[tex]x^{2}+11x-180=0[/tex] and [tex](x+20)(x-9)=0[/tex]
