Solve by factoring.

Question

p squared minus 4 p equals 21

(1 point)
Responses

p equals one fourth or 21
Image with alt text: p equals one fourth or 21

p equals 3 or 7
Image with alt text: p equals 3 or 7

p equals negative 3 or 7
Image with alt text: p equals negative 3 or 7

p equals 3 or negative 7

Answer 1

To solve the equation by factoring:

p^2 - 4p = 21
p^2 - 4p - 21 = 0

Now we need to factor the quadratic equation:
(p - 7)(p + 3) = 0

Setting each factor to zero:
p - 7 = 0
p = 7

p + 3 = 0
p = -3

So the solutions are p = 7 and p = -3.