Respuesta :
Answer:
[tex]2.4 k^5(k+7)=0\\\\ k^5 \times (k+7)=0\\\\ k^5=0 \wedge (k+7)=0\\\\ k=0, \wedge , k=-7\\\\3. g^2+4 g-3=0\\\\g=\frac{-4\pm\sqrt{4^2- 4(-3)(1)}}{2\times 1}\\\\g=\frac{-4\pm\sqrt{28}}{2}\\\\g=-2\pm\sqrt{7}\\\\ 4. s^2-14 s+45=0\\\\ s^2-9 s-5 s+45=0\\\\ s(s-9)-5(s-9)=0\\\\ (s-9)(s-5)=0\\\\ s=9 \wedge,s=5\\\\ 5.2 z^2-21 z-36=0\\\\2 z^2-24 z+ 3 z-36=0\\\\2 z (z-12)+3(z-12)=0\\\\ (2 z +3)(z-12)=0\\\\ (2 z +3)=0 \wedge, (z-12)=0\\\\ z=\frac{-3}{2} \wedge,z=12\\\\6. c^2=5 c\\\\c^2-5 c=0\\\\c(c-5)=0[/tex]
[tex]c=0 \wedge (c-5)=0\\\\ c=0 \wedge c=5\\\\ p^2-4p=21\\\\p^2-4 p -21=0\\\\ p^2-7 p +3 p -21=0\\\\ p(p-7)+3(p-7)=0\\\\ (p+3)(p-7)=0\\\\ p+3=0 \wedge p-7=0\\\\ p=-3 \wedge , p=7\\\\8. 2 w^2-11 w = -12\\\\ 2 w^2-11 w +12=0\\\\2 w^2-8 w-3 w +12=0\\\\2 w(w-4)-3(w-4)=0\\\\ (2 w-3)(w-4)=0\\\\2 w-3=0 \wedge w-4=0\\\\ w=\frac{3}{2} \wedge w=4\\\\9.4 q^2+3 q=3 q^2-4 q+18\\\\ 4 q^2-3 q^2 +3 q + 4 q-18=0\\\\ q^2+7 q -18=0\\\\q^2+9 q-2 q -18=0\\\\ q(q+9)-2(q+9)=0\\\\(q-2)(q+9)=0\\\\ q-2=0 \wedge q+9=0[/tex]
[tex]\\\\ q=2 \wedge q=-9\\\\ 10. A=24 (\text{ft})^2,\text{Let width}=w.{\text{then length}}=w+2\\\\\rightarrow w\times (w+2)=24\\\\ \rightarrow w^2 +2 w -24=0\\\\\rightarrow w^2+6 w -4 w -24=0\\\\\rightarrow w(w+6)-4(w+6)=0\\\\ (w-4)(w+6)=0\\\\ w=4 \wedge w=-6[/tex]
where, A= Area
w ≠ -6
So, width = 4 feet
Length = 4 +2 =6 feet