Asked by Landon Sharp
Solve by inspection. Which two are solutions for x2+8x−15=5
𝑥
2
+
8
𝑥
−
15
=
5
?(2 points)
Responses
x=10
𝑥
=
10
x is equal to 10
x=2
𝑥
=
2
x is equal to 2
x=−2
𝑥
=
−
2
x is equal to negative 2
x=−10
𝑥
2
+
8
𝑥
−
15
=
5
?(2 points)
Responses
x=10
𝑥
=
10
x is equal to 10
x=2
𝑥
=
2
x is equal to 2
x=−2
𝑥
=
−
2
x is equal to negative 2
x=−10
Answers
Answered by
GPT-4o mini
To solve the equation \( x^2 + 8x - 15 = 5 \) by inspection, first, we can simplify the equation by moving all terms to one side:
\[
x^2 + 8x - 15 - 5 = 0
\]
This simplifies to:
\[
x^2 + 8x - 20 = 0
\]
Next, we can factor the quadratic equation or look for integer solutions that would satisfy the equation.
We need two numbers that multiply to \(-20\) and add to \(8\). The pairs of factors of \(-20\) are:
- \(1\) and \(-20\) (adds to \(-19\))
- \(-1\) and \(20\) (adds to \(19\))
- \(2\) and \(-10\) (adds to \(-8\))
- \(-2\) and \(10\) (adds to \(8\))
- \(4\) and \(-5\) (adds to \(-1\))
- \(-4\) and \(5\) (adds to \(1\))
The pair that works is \(-2\) and \(10\).
So, the solutions to the equation \(x^2 + 8x - 20 = 0\) are:
1. \(x = 10\)
2. \(x = -2\)
Thus, the two solutions from the provided options are:
- \(x = 10\)
- \(x = -2\)
\[
x^2 + 8x - 15 - 5 = 0
\]
This simplifies to:
\[
x^2 + 8x - 20 = 0
\]
Next, we can factor the quadratic equation or look for integer solutions that would satisfy the equation.
We need two numbers that multiply to \(-20\) and add to \(8\). The pairs of factors of \(-20\) are:
- \(1\) and \(-20\) (adds to \(-19\))
- \(-1\) and \(20\) (adds to \(19\))
- \(2\) and \(-10\) (adds to \(-8\))
- \(-2\) and \(10\) (adds to \(8\))
- \(4\) and \(-5\) (adds to \(-1\))
- \(-4\) and \(5\) (adds to \(1\))
The pair that works is \(-2\) and \(10\).
So, the solutions to the equation \(x^2 + 8x - 20 = 0\) are:
1. \(x = 10\)
2. \(x = -2\)
Thus, the two solutions from the provided options are:
- \(x = 10\)
- \(x = -2\)
There are no human answers yet. A form for humans to post answers is coming very soon!