Question

Solve by completing the square w^2-10w+21=0

Answer 1

Answer:

The solutions are w=7, w=3

Step-by-step explanation:

we have

$w^2-10w+21=0$

Group terms that contain the same variable and move the constant term to the right side

$w^2-10w=-21$

Complete the square

$w^2-10w+5^2=-21+5^2$

$w^2-10w+25=-21+25$

$w^2-10w+25=4$

Rewrite as perfect squares

$(w-5)^2=4$

take square root both sides

$w-5=(+/-)2$

$w=5(+/-)2$

$w_1=5(+)2=7$

$w_2=5(-)2=3$

therefore

The solutions are w=7, w=3