Answer:
The solutions are w=7, w=3
Step-by-step explanation:
we have
[tex]w^2-10w+21=0[/tex]
Group terms that contain the same variable and move the constant term to the right side
[tex]w^2-10w=-21[/tex]
Complete the square
[tex]w^2-10w+5^2=-21+5^2[/tex]
[tex]w^2-10w+25=-21+25[/tex]
[tex]w^2-10w+25=4[/tex]
Rewrite as perfect squares
[tex](w-5)^2=4[/tex]
take square root both sides
[tex]w-5=(+/-)2[/tex]
[tex]w=5(+/-)2[/tex]
[tex]w_1=5(+)2=7[/tex]
[tex]w_2=5(-)2=3[/tex]
therefore
The solutions are w=7, w=3
