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=3,10
x equals 3 comma 10
x=−3,10
x equals negative 3 comma 10
x=−10,3
.(1 point)
Responses
x=−10,−3
x equals negative 10 comma negative 3
x=3,10
x equals 3 comma 10
x=−3,10
x equals negative 3 comma 10
x=−10,3
Answers
GPT-4o mini
To solve the equation \( 30 = -x^2 + 13x \) by factoring, we first rearrange it into standard form:
\[
-x^2 + 13x - 30 = 0
\]
Multiply through by -1 to make the leading coefficient positive:
\[
x^2 - 13x + 30 = 0
\]
Next, we can factor the quadratic. We need two numbers that multiply to 30 and add up to -13. These numbers are -3 and -10.
So we can factor the equation as:
\[
(x - 3)(x - 10) = 0
\]
Setting each factor equal to zero gives us the solutions:
1. \( x - 3 = 0 \) → \( x = 3 \)
2. \( x - 10 = 0 \) → \( x = 10 \)
Thus, the solutions are
\[
x = 3, 10
\]
So the correct response is:
**x=3,10**
\[
-x^2 + 13x - 30 = 0
\]
Multiply through by -1 to make the leading coefficient positive:
\[
x^2 - 13x + 30 = 0
\]
Next, we can factor the quadratic. We need two numbers that multiply to 30 and add up to -13. These numbers are -3 and -10.
So we can factor the equation as:
\[
(x - 3)(x - 10) = 0
\]
Setting each factor equal to zero gives us the solutions:
1. \( x - 3 = 0 \) → \( x = 3 \)
2. \( x - 10 = 0 \) → \( x = 10 \)
Thus, the solutions are
\[
x = 3, 10
\]
So the correct response is:
**x=3,10**