Question

Li Juan solves the equation below by first squaring both sides of the equation.

Answer 1

-3w + 13
Happy New Year

Answer 2

Answer:

Step-by-step explanation:

(13-2w)^2 = 169 - 52w + 4w^2

(w+6)^2 = w^2 + 12w + 36

Setting them equal:

169 - 52w + 4w^2 = w^2 + 12w + 36

3w^2 - 64w + 133 = 0

Using the quadratic formula, we get

x = (64 +/- sqrt(64^2 - 4*3*133))/6

64^2-12*133 = 2500. sqrt(2500) = 50.

x = (64 +/- 50)/6.

x = 19 or 14/6 = 7/3.

Solving the original equation:

7 = 3w.

w = 7/3.

Therefore 19 is extraneous.