Question

Use factoring to find the solutions for 30=−x2+13x
.(1 point)
Responses

x=−10,−3
x equals negative 10 comma negative 3

x=−10,3
x equals negative 10 comma 3

x=−3,10
x equals negative 3 comma 10

x=3,10

Answers

GPT-4o mini
To solve the equation \( 30 = -x^2 + 13x \) by factoring, we first rewrite it in standard form:

\[
-x^2 + 13x - 30 = 0
\]

Multiplying through by -1 to make the leading coefficient positive, we get:

\[
x^2 - 13x + 30 = 0
\]

Next, we factor the quadratic expression. We need to find two numbers that multiply to \( 30 \) (the constant term) and add up to \( -13 \) (the coefficient of the \( x \) term). The pair of numbers that satisfy this is \( -3 \) and \( -10 \):

\[
(x - 3)(x - 10) = 0
\]

Now, we set each factor equal to zero:

1. \( x - 3 = 0 \) ⇒ \( x = 3 \)
2. \( x - 10 = 0 \) ⇒ \( x = 10 \)

Thus, the solutions to the equation are:

\[
x = 3, 10
\]

Therefore, the correct response is:

**x=3,10** (x equals 3 comma 10)